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The sila-acylation of allenes is performed in the presence of a copper catalyst using PhMe2Si-B(pin) and esters as the silyl and acyl sources, respectively. β-Silyl-β,γ-unsaturated ketones are obtained regioselectively in good to high yields. The sila-imination of allenes is also achieved using nitriles as electrophiles. Exposure of the reaction mixture to air results in the production of cyclic silyl peroxides.

Two series of competitive acylation experiments with a polar and an apolar alcohol substrate, imitating two parts of amphiphilic diols, examined the influence of bases of varying strength on the substrate selectivity. While weakly basic 2,4,6-collidine only mildly accelerates the acylation of the polar substrate without affecting that of the apolar one, the acylation of both substrates is drastically hastened by strongly basic DBU. In both cases there is a notable, though not overwhelming, shift of the substrate selectivity towards the polar substrate, compared to the base-free acylation, which favors that of the apolar one. The extraordinarily strong change in the substrate selectivity in favor of the polar substrate was induced, however, by aliphatic tertiary amine bases, DIPEA and Et3N, of ‘Goldilocks’ moderate base strength, which strongly accelerate the acylation of the polar substrate, while almost not affecting that of the apolar one. These effects of the bases on the substrate selectivity are reflected in the site-selectivity trends observed in the acylation of a model diol amphiphile.

We report an efficient method for the direct β-acylation of 2-ylideneoxindoles with acyl chlorides that is catalyzed by organophosphanes in the presence of base. A variety of functionalized 2-ylideneoxindoles were prepared in moderate to good yields under mild, metal-free conditions via a tandem phospha-Michael/O-acylation/intramolecular cyclization/rearrangement sequence. Mechanistic investigations revealed that C–O bond cleavage on a possible betaine intermediate is the key step for the installation of the keto-functionality at the β-position of 2-ylideneoxindoles in a highly stereospecific manner. The synthetic utility of this protocol could also be proven by a scale-up reaction and synthetic transformations of the products.

Acrylamides are versatile building blocks that are easily obtained from readily available starting materials. During the last 20 years, these valuable substrates bearing a nucleophilic nitrogen atom and an electrophilic double bond have proven to be efficient domino partners, leading to a wide variety of complex aza-heterocycles of synthetic relevance. In this non-exhaustive review, metal-free and metal-triggered reactions followed by an annulation will be presented; these two approaches allow good modulation of the reactivity of the polyvalent acrylamides.1 Introduction2 Metal-Free Annulations2.1 Domino Reactions Triggered by a Michael Addition2.2 Domino Reactions Triggered by an Aza-Michael Addition2.3 Domino Processes Triggered by an Acylation Reaction2.4 Domino Reactions Triggered by a Baylis–Hillman Reaction2.5 Cycloadditions and Domino Reactions2.6 Miscellaneous Domino Reactions3 Metal-Triggered/Mediated Annulations3.1 Zinc-Promoted Transformations3.2 Rhodium-Catalyzed Functionalization/Annulation Cascades3.3 Cobalt-Catalyzed Functionalization/Annulation Cascades3.4 Ruthenium-Catalyzed Functionalization/Annulation Cascades3.5 Iron-Catalyzed Functionalization/Annulation Cascades3.6 Palladium-Catalyzed Functionalization/Annulation Cascades3.7 Copper-Catalyzed Transformations3.8 Transition Metals Acting in Tandem in Domino Processes4 Radical Cascade Reactions5 Conclusion

The process of C–H functionalization has been extensively studied as a direct C–C bond-forming reaction with high atomic efficiency. Efforts have also been made on such reactions by using supported catalysts, which are superior in terms of catalyst separation from the reaction mixture and reusability. In this review, an overview of C–H functionalization reactions, especially those involving Pd- and Au-supported catalysts, is presented. In particular, we discuss reaction mechanisms, active species, leaching, reusability, etc.1 Introduction2 Types of Supported Metal Catalysts and Their Active Species3 Modes of C–H Bond Activation4 Oxidative C–H C–H Coupling of Aryl Compounds5 C–H C–H Coupling Where One Side Is Aromatic6 C–H Acylation of Aromatic Compounds and Related Reactions7 Conclusion

A five-step, practical, and concise total synthesis of mubritinib is described. The synthesis utilized Friedel–Crafts acylation, click reaction, reduction, and demethylation for the construction of the triazole ring system as key steps. Another important feature of this synthesis is the Bredereck oxazole synthesis. The main advantages of this process are the improved yield and decreased number of reaction steps, which paves the way for the industrial-scale synthesis of mubritinib.

Visible-light photoredox catalysis has recently emerged as a powerful tool for the development of new and valuable chemical transformations under mild conditions. Visible-light promoted enantioselective radical transformations of imines and iminium intermediates provide new opportunities for the asymmetric synthesis of amines and the asymmetric β-functionalization of unsaturated carbonyl compounds. In this review, recent advances on the catalytic asymmetric radical functionalization of imines and iminium intermediates are summarized.1 Introduction2 Enantioselective Radical Functionalization of Imines2.1 Asymmetric Reduction2.2 Asymmetric Cyclization2.3 Asymmetric Addition2.4 Asymmetric Radical–Radical Coupling 3 Enantioselective Radical Functionalization of Iminium Ions3.1 Asymmetric Radical Alkylation3.2 Asymmetric Radical Acylation4 Conclusion

A concise and modular synthesis of pyrrolo[1,2-a][1,6]- and [1,8]naphthyridines by a one-pot two-step reaction consisting of electrophilic acylation followed by an alkyne-carbonyl-metathesis reaction as the final cyclization step is reported. This developed synthetic methodology allows the facile synthesis of these heterocyclic core structures in mainly high overall yields under metal-free conditions. Reaction conditions are carefully optimized and display a novel supplement to access these tricyclic heterocyclic compounds.

A versatile palladium-catalyzed C6-selective C–H acylation of 2-pyridones with commercially available aldehydes using TBHP as an oxidant has been developed. This protocol tolerated diverse functional groups and has excellent level of site selectivity. Moreover, it does not require silver salts as additives. 2-pyridones C6-selective palladium catalysis C–H acylation radical

A concise and convergent stereoselective synthesis of curvulone B is described. The synthesis utilized a tandem isomerization followed by C–O and C–C bond-forming reactions following Mukaiyama-type aldol conditions for the construction of the trans-2,6-disubstituted dihydropyran ring system as the key steps. Other important features of this synthesis are a cross-metathesis, epimerization, and Friedel–Crafts acylation.

A highly efficient nucleophilic addition–O-acylation–intramolecular Wittig reaction of β-trifluoromethyl α,β-enones is disclosed. This strategy features mild reaction conditions and provides a practical transition-metal-free method to a set of biologically significant trifluoromethylated furans in high yields with diverse functional groups.

A photocatalyzed intramolecular cyclization is developed for the synthesis of fluorenones. In this photoredox reaction, triphenylphosphine is used as an inexpensive and effective deoxygenative reagent for biarylcarboxylic acids to give acyl radicals, which quickly undergo intramolecular radical cyclization. Reactions in the presence of air and continuous flow photoredox technology demonstrate the generality and practicality of this process.

A novel convenient acid-catalyzed acylation of enaminodiones with acylbenzotriazoles via soft enolization has been developed for the direct synthesis of hard-to-reach 5-acyl-3-oxy-4-pyrones. The important advantages of the reaction include broad substrate scope, mild conditions, scalability, and readily isolation of products by crystallization without the use of chromatography. Further modification of the pyrone ring and synthesis of various azaheterocycles via ring-opening transformation have been demonstrated for the preparation of potential scaffolds for inhibition of metalloenzymes.

3-(Thien-2-yl)- and 3-(thien-3-yl)allylamines, readily accessible from the corresponding thienyl aldehydes, can interact with a broad range of anhydrides and α,β-unsaturated acids chlorides (maleic, сitraconic­, and phenyl maleic anhydrides, сrotonyl and сinnamyl chlorides, etc.) leading to the formation of a thieno[2,3-f]isoindole core. Usually, the reaction sequence involves three successive steps: acylation of the nitrogen atom of the initial allylamine, the intramolecular Diels–Alder vinylarenе (IMDAV) reaction, and the final aromatization of the dihydrothiophene ring in the Diels–Alder adducts. The scope and limitations of the proposed method were thoroughly investigated. It was revealed with the aid of X-ray analysis that the key step, the IMDAV reaction, proceeds through an exo-transition state, giving rise to the exclusive formation of a single diastereomer of the target heterocycle. In the case of maleic anhydrides, the method allows to obtain functionally substituted thieno[2,3-f]isoindole carboxylic acids, which are potentially useful substrates for further transformations and subsequent bioscreening.

An efficient palladium-catalyzed C–H bond functionalization/ortho-monoacylation reaction of 3-aryl-1,2,4-benzotriazines with (hetero)aryl or alkyl aldehydes has been developed, which offers a facile and alternative strategy for direct modification and further diversification of 3-aryl-1,2,4-benzotriazines. Bioactive 1,2,4-benzotriazine has been employed as a novel directing group for the palladium-catalyzed regioselective monoacylation of sp2 C–H bond protocol with broad substrate scope and good functional group tolerance.

An efficient catalyst-free radical cross-coupling reaction between aromatic aldehydes and sulfoximines was developed. The reaction took place in the presence of N-bromosuccinimide as the radical initiator under microwave irradiation to afford the corresponding acylated sulfoximines in moderate to excellent yields (27 examples). This protocol proved to be rapid, easy to handle, and applicable to a broad scope of substrates.

A convenient ultrasound-assisted one-pot synthesis of N-acylcyanamides starting from readily available carboxylic acids and sodium cyanamide has been developed. Upon activation in the presence of trichloroisocyanuric acid (TCCA) and triphenylphosphine, a range of carboxylic acids was converted into N-acylcyanamides in good to excellent yields within 10 minutes at room temperature without base. Remarkably, N-acyl-substituted imidazolones were readily accessible through guanylation-cyclization of the in situ generated N-acylcyanamides.

The tandem acylation reactions of 2-quinolylzincates under one-pot reaction conditions facilitated the formation of biologically active (Z)-3-alkylidenephthalides and multifunctionalized quinoline derivatives at specific positions. The reactions of these zincates with allyl iodide produced three different types of temperature- and alkyl-ligand-dependent C-2 homologated quinolines. The reaction mechanisms for the formation of the presented products from 2-quinolylzincates are also proposed in detail.

An efficient and practical synthetic protocol for the synthesis of 1,4-disubstituted pyrrolo[1,2-a]pyrazine derivatives is described that originates from α-substituted pyrroloacetonitriles which, in turn, are readily available from aryl and alkyl aldehydes. The α-pyrroloacetonitriles were subjected to a Friedel–Crafts acylation with methyl chlorooxoacetate followed by reduction of the nitrile group under Pd-catalyzed hydrogenation conditions and finally aromatization with DDQ leading to the desired pyrrolo[1,2-a]pyrazine derivatives. This method was generalized and successfully applied to various aryl, heteroaryl, and alkyl substrates. The developed protocol provides direct and convenient access to 1,4-disubstituted ring systems in moderate to good overall yields (51–68%) without the need for purification of the intermediates. Further functionalization via the stepwise halogenation (bromination, iodination) and nitration was also demonstrated. In addition, the potential of the ester functionality for elaboration was demonstrated by manipulating into heterocyclic ring systems, exemplified by conversion into benzoxazole derivatives.

Piperazine derivatives containing 1,1′-bi-2-naphthyl moiety were synthesized starting from 2,2′-dimethoxy-1,1′-bi-naphthalene via acylation using ethyl chlorooxoacetate and subsequent condensation with 1,2-diamines followed by reduction of the corresponding dihydro-2-piperazinone intermediate using the NaBH4/I2 reagent system. The corresponding chiral piperazine derivatives containing bi-2-napthyl moiety was synthesized by asymmetric reduction of ethyl dimethoxy-bi-2-naphthyloxoacetate by chiral oxazoborolidine catalyst prepared in situ using S-diphenylprolinol (S-DPP), B(OCH3)3 and H3B·THF. The resulting diols were mesylated and cyclized using 1,2-diamines to obtain the corresponding chiral piperazine derivatives.

Site-selective reactions of water-soluble biomolecules are being developed to produce efficient conversions in water and water­/solvent mixtures. This review focuses on the use of designs based on bis-bidentate chelation of large metal ions by diols to be acylated by a co-chelated water-stable reagent. Topics discussed include: 1. The preparation and properties of water-stable acyl phosphate monoesters and their reactions with diol-chelated metal ions. 2. Site-selective monoaminoacylation of 3′-terminal diols of RNA and their applications in protein engineering. 3. Site-selective monoacylation of sugars with acyl phosphate monoesters associated with metal ions, including lanthanum and lead. The combination of metal ion, 1,2-diol, and acyl phosphate monoester produces site-selective reactions in aqueous media­ that can produce a general approach to site-selective mono-(amino)acylation in RNA and carbohydrates.1 Introduction2 Synthetic Aminoacylation of tRNA3 Activated Amino Acids in Water4 Metal Ions and Their Effects on the Reactivity of Acyl Phosphate Monoesters5 The Challenge of Site-Selective Acylation of Carbohydrates in Water6 Conclusions and Prospects

Authors thank the EPSRC Centre for Doctoral Training in Critical Resource Catalysis (CRITICAT, grant code EP/L016419/1, R.M.N.) for funding. We thank the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007–2013) ERC grant agreement no. 279850 (A.D.S.). A.D.S. thanks the Royal Society for a Wolfson Research Merit Award. The isothiourea-catalysed acylative kinetic resolution of a range of acyclic (±)-1,2-diols using 1 mol% of catalyst under operationally simple conditions is reported. Significantly, the bifunctional nature of (±)-1,2-diols was exploited in a sequential double kinetic resolution, in which both kinetic resolutions operate synergistically to provide access to highly enantioenriched products. The principles that underpin this process are discussed, and selectivity factors for the individual kinetic resolution steps are reported in a model system. Postprint

1-Nicotinoylbenzotriazole (NicBt) was uncovered as an efficient protecting agent for the site-selective acylation of resorcinol-type phenolic groups with almost equal reactivity. The use of NicBt allows selective protection of the 7-OH group in 5,7-dihydroxycoumarins in one simple scalable step, while combination of the nicotinoylation with tosylation–denicotinoylation or silylation–denicotinoylation yields 5-OH-protected 5,7-dihydroxycoumarins. Furthermore, nicotinoylated 5,7-dihydroxycoumarins proved useful in a gram-scale three-step preparation of a 2,2-dimethylpyrano[2,3-f]coumarin, a key intermediate for the synthesis of calanolide A, an HIV reverse transcriptase and Mycobacterium tuberculosis inhibitor, and its active analogues.

The reactions of t-Boc-protected secondary and primary amines with difluorocarbene generated from trimethylsilyl (fluorosulfonyl)difluoroacetate [Me3SiOC(O)CF2SO2F] (TFDA) in toluene at 110 °C results in the replacement of t-Bu by difluoromethyl in the t-Boc group. This reaction can be carried out in the presence of CH2Br and COOMe moieties in the structure of the protected amine. In the example of a t-Boc-protected amine containing a C=C double bond, replacement of the t-Bu group and/or cyclodifluoropropanation takes place. Difluoromethyl esters are shown to react with primary and secondary amines yielding the corresponding ureas.

Visible-light photoredox catalysis enables easy access to acyl radicals under mild reaction conditions. Reactive acyl radicals, generated from various acyl precursors such as aldehydes, α-keto acids, carboxylic acids, anhydrides, acyl thioesters, acyl chlorides, or acyl silanes, can undergo a diverse range of synthetically useful transformations, which were previously difficult or inaccessible. This review summarizes the recent progress on visible-light-driven acyl radical generation using transition-metal photoredox catalysts, metallaphotocatalysts, hypervalent iodine catalysts or organic photocatalysts.1 Introduction2 The Scope of This Review3 Aldehydes as a Source of Acyl Radicals4 α-Keto Acids as a Source of Acyl Radicals5 Carboxylic Acids as a Source of Acyl Radicals6 Anhydrides as a Source of Acyl Radicals7 Acyl Thioesters as a Source of Acyl Radicals8 Acyl Chlorides as a Source of Acyl Radicals9 Acyl Silanes as a Source of Acyl Radicals10 Conclusions and Future Outlook

A simple protocol for the synthesis of 2-acylbenzothiazoles using aryl ketones and benzothiazoles in the presence of I2 and TBHP is described. Acylation of the benzothiazoles is achieved through a sequence involving oxidation of the aryl ketone to an aryl glyoxal, ring-opening of the benzothiazole followed by condensation of the amino group with the aryl glyoxal, cyclization and oxidation. The method avoids the use of metals and toxic solvents. In addition, this protocol has the advantage of broad scope and provides good to excellent product yields.

A bis-acylation strategy to access functionalized anthraquinones via one-pot relay process, is presented. The first acylation was feasible under [Pd]-catalyzed intermolecular direct acylation reaction, while, the second acylation was accomplished by using intramolecular Friedel–Crafts acylation. Notably, benchtop aldehydes have been utilized as non-toxic acylation agents in the key [Pd]-catalyzed acylation.

This account focuses on our work in palladium/norbornene-catalyzed selective ortho-arylation and ortho-acylation of aryl halides. It will discuss our synthetic plan, initial design and revised strategy in the enantioselective synthesis of the rhazinal family of natural products. It also shows our efforts on the α-acylation reaction by the cleavage of various C(O)–X bonds, along with some mechanistic studies.1 Introduction2 Synthesis of the Rhazinal Family of Natural Products2.1 Initial Design2.2 Revised Strategy2.3 Enantioselective Synthesis of the Rhazinal Family of Natural Products3 Catalytic ortho-Acylation3.1 Acid Chloride and Anhydride Strategy3.2 Cleavage of C(O)–S Bond of Thioesters by Pd, Norbornene and Copper Cocatalysis4 Decarboxylative Alkynylation5 Conclusion

Efficient S-acylation of thiourea using a variety of acid chlorides is reported. Structurally diverse aryl and alkyl substrates are compatible with this methodology. Confirmation that acylation occurs exclusively­ on the sulfur atom of thiourea is provided by single-crystal X-ray crystallographic analysis.

A convenient two-step, one-pot synthesis of 4-chloro-2-(trichloromethyl)pyrimidines starting from 2-(trichloromethyl)-1,3-diazabutadienes is described. These nitrogen heterocycles were prepared by a sequential acylation/intramolecular cyclization reaction between 2-(trichloromethyl)-1,3-diazabutadienes and acyl chlorides in the presence of triethylamine followed by treatment with POCl3. This is the first report for the synthesis of this type of 4-chloro-2-(trichloromethyl)pyrimidine derivatives and serves as a source for a wide variety of other substituted pyrimidines by nucleophilic substitution reactions.

The N-acylation of indoles has been accomplished via inorganic base catalysis. It provided an efficient and simple catalysis system for the preparation of N-acylindoles with alkenyl carboxylates as acylating agents. A broad variety of indoles undergo the smooth N-acylation using Na2CO3 as catalyst in MeCN at 120 °C to give the corresponding N-acylindoles in good to excellent yields.

Inorganic base-catalyzed O-acylation of phenol and its derivatives has been developed. The procedure provides an efficient catalysis system for the preparation of aryl carboxylates with alkenyl carboxylates as acyl reagents. The reaction proceeded smoothly by using ­Na2CO3 as the catalyst in MeCN to produce the corresponding aryl carboxylates in good to excellent yields.

Nucleophilic acylation of symmetrical carboxylic anhydrides has inherited limitation of reaction efficiency along with relatively poor reactivity. Traditionally, one equivalent carboxylic acid is generated during nucleophilic acylation of a symmetrical anhydride, which always limits the yield of final product to 50% or less. This is a major drawback, which discourages the use of anhydrides for laboratory or industrial applications. Electrophilic activation of carboxylic anhydride using methanesulfonyl chloride is found to be an efficient method for nucleophilic acylation, which increases product yield by restricting the formation of corresponding acid as a side product. The developed protocol found to be a mild and high yielding methodology for one-pot nucleophilic acylation of carboxylic anhydrides with several type of N- and S-nucleophiles demonstrating appreciable functional group tolerance.

A mild, environmentally friendly, and regioselective acylation of heterocycles with inexpensive carboxylic acids is reported via photoredox catalysis. The strategy is highlighted with good functional group tolerance and substrate scope which could rapidly realize the acylation of various heterocyclic compounds.

An efficient, general synthetic protocol for the synthesis of the biologically active benzofurans ailanthoidol, egonol and homoegonol was developed. The key starting material, eugenol, is a naturally occurring and abundant precursor. The protocol, involving sequential acylation and intramolecular Wittig reaction, provides a convenient method for building the benzofuran moiety in good yield.

Acylation of 4-alkylpyridines with 2-iodobenzoyl chlorides under basic conditions results in pyridine dearomatization via formation of 4-alkylidene dihydropyridines. These reasonably stable intermediates are further transformed through Pd-catalyzed Mizoroki–Heck cyclization to afford dihydropyrido-fused isoindolinone products in good yield. This study demonstrates successful harnessing of reactive dearomatized pyridine anhydrobases in metal-catalyzed C–C bond-forming reactions, and provides an efficient entry to isoindolinone ring systems structurally related to several indolizidine alkaloid frameworks.

An efficient palladium-catalyzed decarboxylative selective C–H acylation is reported using α-oxocarboxylic acids as the acyl source directed by 1,2,3-triazole ring. This method provides a novel access to various 1,2,3-triazole derivatives bearing diaryl ketone skeleton.

The fast and biocompatible ligation of 1,2,4,5-tetrazines with strained alkenes has found numerous applications in biomedical sciences. The reactivity of a 1,2,4,5-tetrazine can generally be tuned by changing its electronic properties by varying the substituents in the 3- and/or 6-position. An increased reactivity of such bioorthogonal probes upon conjugation or attachment to a target molecule has not previously been described. Such an approach would be beneficial, as it would minimize the impact of residual tetrazine reagents and/or impurities. Herein, we describe such a ‘kinetic turn-on’ of 1,2,4,5-tetrazines upon conjugation. On the basis of the significant increase in reactivity following N-acylation predicted by quantum chemical calculations, we prepared 3-aminotetrazines and their corresponding acetylated derivatives. An investigation of the reaction kinetics indeed revealed a remarkable increase in reactivity upon acylation.

An efficient synthesis of benzhydrazides has been achieved through the direct acylation of azodicarboxylates with benzylic alcohols in moderate to high yields. The method represents the first practical approach to amides containing a hydrazine structural unit from benzylic alcohols.

To explore further the practical uses of highly active manganese (Mn*), a variety of alcohols were treated with Mn*, and the resulting complexes were coupled with acid chlorides and/or acetic anhydride in the absence of any extra catalyst. The subsequent reactions took place smoothly under mild conditions, providing the corresponding O-acylation products in good to excellent isolated yields.

A facile, superacid-promoted, domino, one-pot synthesis of novel spirotetracyclic indanones through intramolecular Friedel–Crafts acylation/alkylation of α,β-unsaturated cinnamic acid esters is presented. Interestingly, when the β-aryl group contained electron-withdrawing substituents such as fluoro, chloro, or bromo, the reaction took a different mechanistic path and afforded arylindenes as the end products.

In a recent study, several new derivatives of antimycin A (AMA) were produced by means of a novel transacylation reaction, and these were shown to mediate selective toxicity toward cultured A549 human lung epithelial adenocarcinoma cells, as compared with WI-38 normal human lung fibroblasts. The purpose of our study was to investigate whether the analogues all expressed their cytotoxicity by the same mechanism. This was done by studying the effects of the compounds in several types of cell lines. In comparison with 2-O-methylantimycin, which acts at the locus of Bcl-2, none of the new derivatives exhibited a difference in cytotoxicity toward cells expressing different levels of Bcl-2. In cell lines that over- or underexpress estrogen or Her2 receptors, AMA analogue 2 exhibited Her2 receptor dependency at low concentration. Three compounds (1, 4, and 6) exhibited concentration-dependent increases in reactive oxygen species, with 6 being especially potent. Compounds 5 and 6 diminished mitochondrial membrane potential more potently than AMA, and 1 also displayed enhanced activity relative to 2–4. Interestingly, only 1 and AMA displayed strong inhibition of the respiratory chain, as measured by monitoring NADH (reduced nicotinamide adenine dinucleotide) oxidase. Because four of the analogues have positively charged substituents, two of these (4 and 6) were studied to see whether the observed effects were due to much higher level of accumulation within the mitochondria. Their presence in the mitochondria was not dramatically enhanced. Neither of the two presently characterized mechanisms of cell killing by AMA can fully account for the observed results.

An efficient approach to bridged pentacyclic nitrogen heterocycles via the tandem acylation/intramolecular Diels–Alder furan (IMDAF) reaction of 2-furylquinazolinones is described. Reactions of α,β-unsaturated acid anhydrides with 2-furyl-2,3-dihydroquinazolin-4-ones give 6b,9-epoxyisoindolo[2,1-a]quinazolines in average yields. In this case, the exo-IMDAF reactions proceed with excellent diastereoselectivity giving five stereogenic centers and three new rings in one synthetic step. Isomeric 2,4a-epoxyisoindolo[1,2-b]quinazolines are obtained by one-pot, three-component condensation reactions of allylamine, isatoic anhydride and furaldehydes involving the same IMDAF­ reaction as the key step. Some useful transformations including halogenation, hydrogenation, Prilezhaev epoxidation, and esterification of the synthesized epoxyisoindoloquinazolines are also demonstrated.

A wide range of chemicals such as amides, hydrazides, amines, alcohols, carbazate, and sulfonate were reacted with acyl isocyanates generated by the reaction of primary amides with oxalyl chloride to give symmetrical and unsymmetrical diacyl urea derivatives, acyl ureas/carbamates/thiocarbamates, and related compounds. This method provides means for convenient one-pot, two-step synthesis of compounds bearing urea, carbamate, and other functional groups from cheap and commercially available starting reagents. It is expected that the results presented in this report will expand the medicinal chemist’s toolbox.