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An efficient approach to access functionalized (2,3-dihydroisoxazol-4-yl) ketones has been developed by reacting nitrones 4 with ynones 7 or terminal ynones 10 in a one-pot fashion. The reaction went through a formal Sc(OTf)3-catalyzed [3 + 2]-cycloaddition process to generate a number of functionalized (2,3-dihydroisoxazol-4-yl) ketones 11aa–11aw, 11ba–11la and 12aa–12ae in moderate to good yields.

An asymmetric synthesis of 14-methyl-1-octadecene, the sex pheromone of the peach leafminer moth has been achieved. Based on the asymmetric methylation of chiral (S)-4-benzyloxazolidin-2-one, the carbon chain of the target molecule was assembled through a C1+C10+C4+C3 procedure. The γ-lactone was transformed into 4-(benzyloxy)butanoic acid and then, with the induction of Evan’s template, a chiral methyl group was introduced to the position of the carboxylic group in 97% de. After reduction and a couple of chemical operations, the designed key intermediate A1 was obtained. The synthesis of another moiety was started from decane-1,10-diol which was selectively protected and oxidized. The long carbon chain was installed according to a Wittig protocol. After deprotection, oxidization, and methylenation, the target molecule was synthesized in 7 linear steps with an overall yield of 30.3%.

An efficient approach to access functionalized (2,3-dihydroisoxazol-4-yl) ketones has been developed by reacting nitrones 4 with ynones 7 or terminal ynones 10 in a one-pot fashion. The reaction went through a formal Sc(OTf)3-catalyzed [3 + 2]-cycloaddition process to generate a number of functionalized (2,3-dihydroisoxazol-4-yl) ketones 11aa-11aw, 11ba-11la and 12aa-12ae in moderate to good yields.

A straightforward route toward construction of α-quaternary chiral β-lactam moiety via Rh(II)/Pd(0)-catalyzed stereoselective relay catalytic reaction is reported. This asymmetric dual relay catalysis involves Rh(II)-catalyzed enantioselective intramoluecular C–H insertions of α-diazoamides, and sequential Pd(0)-catalyzed diastereoselective intermolecular allylic alkylation. Under mild reaction conditions, a broad range of α-quaternary allylated chiral β-lactams have been synthesized in high yields (up to 99%) with excellent stereoselectivities [up to diastereomeric ratio (dr) >99:1, up to 98% enantiomeric excess (ee)].

A concise asymmetric total synthesis of the sex pheromone of the tea tussock moth has been achieved from commercially available starting materials. The chiral moiety was introduced by Evans’ template and the key C C bond construction was accomplished through Julia-Kocienski coupling and Wittig olefination. The salient characteristic of our synthetic route is that it is protecting a group free.

The ring closure of 2-iodo diaryl ether in the presence of a palladium catalyst to xanthone under carbon monoxide atmosphere is studied. A series of xanthones could be successfully obtained through this protocol, with Pd(OAc)2 as the catalyst, P(Cy)3 as ligand, PivONa.H2O as base, and PivOH and tetrabutylamonium bromide as additives in DMSO, in moderate to good yields.

According to our retrosynthesis, the main chain of the target molecule could be constructed using a C5 + C7 + C5 strategy. The key induction reaction afforded chiral methyl group moieties using different Evans templates with different configurations. Li 2 CuCl 4 was effectively employed in the Csp 3 Csp 3 coupling protocol. The target molecular was obtained in a 12.6% overall yield with nine steps in the longest linear route.

An asymmetric synthesis of 14-methyl-1-octadecene, the sex pheromone of the peach leafminer moth, has been efficiently achieved. A key chiral intermediate, ( R)−4-(benzyloxy)−3-methylbutanal, which has been developed as the resource chemical, can be obtained in large quantities from the steroid industry. 1,11-Undecanediol is selectively masked, and then converted into a phosphonium salt derivative, thereby effectively constructing a carbon skeleton. The target molecule is synthesized in 8 linear steps, with a 42% yield. The key characteristic of our synthesis lies in its chiral-pool strategy.

An efficient method for asymmetric synthesis of epohelmins A (3), B (4) and their isomer 24 is detailed in this report. The key feature in this divergent synthesis includes the SmI2-induced cross-coupling of N-tert-butanesulfinyl imine 10 with chiral aldehyde 9 derived from d -malic acid. A cascade cyclization to the pyrrolizidine skeleton is achieved in our synthetic route for epohelmins. In addition, an interesting intramolecular oxa-Michael addition was observed for epohelmin A (3).

The [Ni(IMes)2]-catalyzed transformation of fluoroarenes into arylboronic acid pinacol esters via C-F bond activation and transmetalation with bis(pinacolato)diboron (B2pin2) is reported. Various partially fluorinated arenes with different degrees of fluorination were converted into their corresponding boronate esters.

An efficient palladium catalyzed C-H bond activation for the synthesis of benzo[c]chromen-6-ones using diazonium salts is described. In the presence of Pd(OAc)2, dppp, PivOH and K2CO3, the diazonium salt can be transformed into the product through a denitrogenation/C-H bond activation/cyclization sequence in acetonitrile. Altogether, nine structurally diverse substituted benzoLc]chromen-6-ones were prepared in excellent yields through two different methods.

Synthesis of the sex pheromone of the tea tussock moth in 33% overall yield over 10 steps was achieved. Moreover, the chiral pool concept was applied in the asymmetric synthesis. The synthesis used a chemical available on a large-scale from recycling of wastewater from the steroid industry. The carbon skeleton was constructed using the C4+C5+C8 strategy. Based on this strategy, the original chiral center was totally retained.

A convergent synthesis of four stereoisomers of the sex pheromone of the western corn rootworm (8-methyldecan-2-yl propionate, 1) from commercially available chiral starting materials is reported. The key step was Julia–Kocienski olefination between chiral BT-sulfone and chiral aldehyde. This synthetic route provided the four stereoisomers of 1 in 24–29% total yield via a six-step sequence. The simple scale-up strategy provides a new way to achieve the asymmetric synthesis of the sex pheromone.

C8H8N2O4, monoclinic, C2/c (no. 15) , a = 27.748(5) Å, b = 5.6488(10) Å, c = 16.437(3) Å, β = 93.393(3)°, V = 2571.87 Å3, Z = 8, R gt(F) = 0.0330, wR ref(F 2) = 0.0963, T = 296(2) K.

An efficient approach for asymmetric synthesis of (+)-spicigerine, (+)-cassine and their 3-epimers has been developed through the intramolecular diastereoselective tandem addition/cyclisation process of α-chiral aldimine 9 with methylmagnesium bromide and the asymmetric addition of nucleophilic reagents to aminal 14. Moreover, the first asymmetric synthesis of (+)-spicigerine has been achieved in this manuscript. In this synthetic strategy, the asymmetric syntheses of (+)-spicigerine and (+)-cassine was achieved in a 14% overall yield and nine steps and an 18% overall yield and seven steps from cheap α-chiral aldimine 9, respectively.

In this work, we designed and synthesized four symmetric and asymmetric thienyl-substituted fluorenone compounds, which all exhibited typical AIE properties. Besides a high solid-state fluorescence quantum yield, the enhanced luminescence of their solid-state powders showed a 170 nm red-shift (from 380 to 550 nm) in comparison with the luminescence of their dilute tetrahydrofuran solutions. The photophysical properties and single-crystal structure, combined with the theoretical calculation, revealed that the bathochromic luminescence is due to the formation of static excimers.

Organic solid-state luminescence materials with aggregation-induced emission enhancement have attracted considerable interest in recent years. In this work, we develop a class of 2,7-diphenylfluorenone derivatives that exhibit prominent aggregation-induced emission properties with high solid-state quantum yields. Their solid-state powders show a ∼160 nm bathochromically shifted fluorescence and longer lifetime compared to their emission in dilute THF solution. The X-ray single structures and photophysical properties reveal that the mechanism of aggregation-induced emission in this class of fluorenone compounds is due to the formation of static excimers through hydrogen bonds in the solid state. The emission of their THF solution peaked at 380 nm and originates from the single molecule and the emission of their solid-state powder peaked at 550 nm originates from the excimers. The aggregation-induced emission properties and luminescence mechanism are further verified by the design of 2,7-diphenylfluorenone-diboronic acid adduct, which exhibited weak luminescence in high pH buffer and red-shifted strong luminescence in acidic buffer.

The one-pot tandem process of ( 2R,4R,S RS )- 15 with Grignard reagents for highly diastereoselective synthesis of functionalized 2-piperidinone 1 was developed. Furthermore, the divergent syntheses of L-685,458 3 and its six analogues 20a – f have been conveniently achieved using this effective protocol as the key step.

Nature has always been recognized as a rich source for the identification of new drug candidates. Heliannuols have drawn wide attention because of their interesting structural scaffolds and biological potential. Biological evaluation has shown that heliannuols have the allelopathic activity and may be used as lead compounds in herbicides. The synthesis of this family of molecules has always been challenging because of their unique scaffold and multiple chiral centers. Up to now, there have been 32 synthetic routes toward these kinds of natural compounds and a mini-review; however, the synthesis of heliannuols F, I, and J have not been reported yet. Many different strategies such Julia coupling, Dickman condensation, ring-closing metasis, ring contraction or expansion, rearrangement, and intramolecular epoxide opening have been employed in these syntheses. More efficient and highly enantiocontrolled and ecofriendly strategies should be developed for sustainable chemistry.

A highly diastereoselective approach for the synthesis of trans-4-hydroxy-5-substituted 2-pyrrolidinones has been developed through an intramolecular cascade process of α-chiral aldimines using alkyl, aryl, alkynyl, and alkenyl Grignard reagents. The stereochemistry at the C-5 position of 2-pyrrolidinone after reaction with alkyl, aryl, and alkenyl Grignard reagents was solely controlled by α-alkoxy substitution. For alkynyl Grignard reagents, the stereochemistry was controlled by coordination of the α-alkoxy substitution and the stereochemistry of the sulfinamide. The utility of this one-pot cascade protocol is demonstrated by the asymmetric synthesis of streptopyrrolidine 5 and 3-epi-epohelmin A 3-epi-6.

The diastereoselective nucleophilic addition of organic boronic ester to 3-hydroxy-2-substituted N -acyliminium ions 9 led to the formation of 2,5- cis -pyrrolidine 10 , from which a convenient synthesis of (−)-7a- epi - 1 was developed. In addition, an efficient asymmetric synthesis of (−)-hyacinthacine A1 1 was achieved through the reduction/ring-opening process.

A diastereoselective one-pot approach to access trans-5-hydroxy-6-substituted-2-piperidinones by an addition-cyclization-deprotection process has been developed, in which the stereogenic center at the C-6 position was solely controlled by α-OTBS group. The utility of this transformation is demonstrated by the asymmetric synthesis of the enantiomer of (-)-CP-99,994.

A series of diaryl amines, ethers and thioethers were synthesized under microwave irradiation efficiently at presence of KF/Al2O3 in 83%–96% yields without any solvent. The salient characters of this method lie in short reaction time, high yields, general applicability to substrates and simple workup procedure. At the same time, their antifungal biological activities against six phytopathogen were evaluated. Most of the compounds (3b, 3c, 3g–o) are more potent than thiophannate-methyl against to Magnaporthe oryzae. This implies that diaryl amine or ether moiety may be helpful in finding a fungicide against Magnaporthe oryzae.

A novel one-pot method for the diastereoselective synthesis of trans-4-hydroxy-5-substituted 2-pyrrolidinones via intramolecular cascade reaction of a series of Grignard reagents is presented.

A highly efficient palladium-catalysed phenyl diazonium tetrafluoroborate participation of C–H activation ring closure protocol has been developed. A series of 6H-benzo[c]chromenes have been synthesized by intramolecular cyclization of ortho diazonium salts tetrafluoroborate of benzyloxyphenyl (Method A), or phenoxymethyl phenyl (Method B). The transformation allows the synthesis of 6H-benzo[c]chromenes with a wide variety of functional groups and substitution patterns from simple and easily accessible precursors.

A series of symmetrical and asymmetrical (multi)branched truxene derivatives have been synthesized by incorporating different π-conjugated functional groups to truxene. Linear absorption and single- and two-photon excited fluorescence properties of the obtained compounds were examined. The spectral data combining the results of theoretical calculation and the X-ray crystal structures demonstrate that the intramolecular charge transfer of the C3-symmetric truxene-core compounds keep independence of every branch and shifts site-to-site upon excitation. The asymmetric molecule SN behaves the intramolecular excitation transfer between more than two energy levels, which maybe different from the symmetric ones. Meanwhile, the C3-symmetric octupolar conformation and the C(sp2) = C(sp2) π-linker are effective structural pattern for two-photon absorption compounds.

A facile total synthesis of three members of the bisabolane sesquiterpene family, namely (±)-curcumene, (±)-xanthorrhizol and (±)-curcuhydroquinone had been achieved in high overall yield. The synthesis used bromobenzene derivatives as starting materials. The halogen-lithium exchange followed by addition of isoprenylacetone and reduction of the obtained carbinols are the key steps of the synthetic pathway. This synthetic approach provides a new route to the bisabolane sesquiterpenes.

A series of xanthones with the dibenzo-γ-pyrone framework were synthesized through the palladium-catalyzed carbonylation/C–H activation sequence from the ortho diazonium salts of diaryl ethers in moderate to excellent yields. After screening the reaction condition, the optimal condition was 5 mol % tetrakis (triphenylphosphine) palladium (0) as the catalyst, potassium carbonate as the base, and toluene as the solvent in the presence of catalytic amount of tetrabutyl ammonium bromide under carbon monoxide atmosphere.

The syntheses of (±)-curcuphenol 1, (±)-curcudiol 2, (±)-curcuhydroquinone 3, and (±)-curcuquinone 4 have been achieved. The key steps involved in the syntheses were the Reformatsky reaction and hydrogenation reaction.

The synthesis of (±)-curcuphenol 1, (±)-curcudiol 2, (±)-curcuhydroquinone 3 and (±)-curcuquinone 4 had been achieved, in which the Johnson-Claisen rearrangement was used as key step.

An efficient and practical demethylation of ortho substituted aryl methyl ethers using AlCl3 has been developed. This method gives a high conversion, is simple to operate and is cost-effective. A mechanism involving the complexation of AlCl3 with the OMe and the adjacent electron withdrawing group is proposed. Many functional groups can be tolerated in the demethylation process, and 29 examples gave a demethylated product in a yield of 90–98%.

An efficient diastereoselective approach to access trans-5-hydroxy-6-alkynyl/alkenyl-2-piperidinones has been developed through nucleophilic addition of α-chiral aldimines using alkynyl/alkenyl Grignard reagents. The diastereoselectivity of alkenyl in C-6 position of 2-piperidinone was controlled by α-alkoxy substitution, while the alkynyl was controlled by the coordination of the α-alkoxy substitution and stereochemistry of sulfinamide. The utility of this straightforward cascade process is demonstrated by the asymmetric synthesis of the (−)-epiquinamide and (+)-swainsonine.

An efficient diastereoselective approach to access trans-5-hydroxy-6-alkynyl/alkenyl-2-piperidinones has been developed through nucleophilic addition of α-chiral aldimines using alkynyl/alkenyl Grignard reagents. The diastereoselectivity of alkenyl in C-6 position of 2-piperidinone was controlled by α-alkoxy substitution, while the alkynyl was controlled by the coordination of the α-alkoxy substitution and stereochemistry of sulfinamide. The utility of this straightforward cascade process is demonstrated by the asymmetric synthesis of the (−)-epiquinamide and (+)-swainsonine.

A series of xanthones with the dibenzo-γ-pyrone framework were synthesized through the palladium-catalyzed carbonylation/C–H activation sequence from the ortho diazonium salts of diaryl ethers in moderate to excellent yields. After screening the reaction condition, the optimal condition was 5 mol % tetrakis (triphenylphosphine) palladium (0) as the catalyst, potassium carbonate as the base, and toluene as the solvent in the presence of catalytic amount of tetrabutyl ammonium bromide under carbon monoxide atmosphere.

Nature has always been recognized as a rich source for the identification of new drug candidates. Heliannuols have drawn wide attention because of their interesting structural scaffolds and biological potential. Biological evaluation has shown that heliannuols have the allelopathic activity and may be used as lead compounds in herbicides. The synthesis of this family of molecules has always been challenging because of their unique scaffold and multiple chiral centers. Up to now, there have been 32 synthetic routes toward these kinds of natural compounds and a mini-review; however, the synthesis of heliannuols F, I, and J have not been reported yet. Many different strategies such Julia coupling, Dickman condensation, ring-closing metasis, ring contraction or expansion, rearrangement, and intramolecular epoxide opening have been employed in these syntheses. More efficient and highly enantiocontrolled and ecofriendly strategies should be developed for sustainable chemistry.