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Abstract Aminocarbonylation of alkenyl and (hetero)aryl iodides using medium-sized 3-aminolactams as N -nucleophiles was carried out in the presence of in situ palladium(0) catalysts. While the iodoalkenes were converted to the corresponding carboxamide under mild reaction condition (1 bar of CO, 50 °C) by using Pd(OAc) 2 /PPh 3 catalysts, the iodobenzene shown decreased reactivity (39% conversion after 2 days) under the similar reaction conditions in the presence of 3-aminoazepan-2-one. The reactivity of iodobenzene and other iodo(hetero)aromatic substrates was increased with 3-aminoazepan-2-one under high (40 bar) carbon monoxide pressure, but the chemoselectivity was shifted towards the 2-ketocarboxamides formed via double carbon monoxide insertion (except 2-iodopyridine). Changing triphenylphosphine to Xantphos, the expected carboxamides were chemoselectively formed in all cases when iodo(hetero)aryl substrates were used in the presence of all of the three 3-aminolactams under mild reaction conditions. The products synthesized in the reactions mentioned above were isolated in moderate to high yields. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Elatine gussonei (Sommier) Brullo et al. is a rare freshwater plant previously assumed to be endemic to Lampedusa and the Maltase archipelago. Taxonomic uncertainties within the Elatine genus may have caused E. gussonei populations to be overlooked in the Mediterranean region. To clarify the distribution of E. gussonei , we reviewed Elatine specimens from 12 herbaria and conducted eight field surveys in Mediterranean countries. Through our herbarium review we documented previously unknown occurrences of E. gussonei from Portugal, Spain, France, Algeria, Egypt, Cyprus and Israel. Additionally, in field studies we found populations from Cyprus, Morocco and Spain. Elatine gussonei is therefore more widespread than previously assumed, although the species still has a scattered distribution around the Mediterranean and many of the records are old. We found intact E. gussonei seeds in the faeces of migratory Greylag Geese ( Anser anser ) collected in southern Spain, suggesting that E. gussonei has a high capacity for long distance dispersal. [ABSTRACT FROM AUTHOR]

The aminocarbonylation of 2,5- and 2,3-diiodopyridine, as well as 2-chloro-3,4-diiodopyridine with carbon monoxide and various primary and secondary amines was carried out using palladium-catalysed aminocarbonylation. The formation of the products containing carboxamide and ketocarboxamide functionalities was accompanied by the formation of imides when ortho -diiodo compounds were used as substrates. In spite of several possible reaction pathways, most of the products were synthesised as major product in yields of synthetic interest by the appropriate modification of the reaction conditions. [ABSTRACT FROM AUTHOR]

Palladium-catalysed aminocarbonylation of iodopyridine model compounds (4-amino-3-iodopyridine and 3-amino-4-iodopyridine) with various primary and secondary amines including amino acid methyl esters was carried out. The two substrates behave in a completely different manner under aminocarbonylation conditions: 4-amino-3-iodopyridine gave the corresponding 2-ketocarboxamides (nicotinamide analogues) due to double carbon monoxide insertion, while 3-amino-4-iodopyridine reacted as a bifunctional substrate resulting in a dicarboxamide containing two pyridyl moieties. [ABSTRACT FROM AUTHOR]

Palladium-catalysed aminocarbonylation of 7-iodoindole derivatives (the parent compound and 5-bromo-7-iodoindole), as well as 5-iodoindole with various primary and secondary amines, including amino acid esters and chiral diamines, was carried out. In this way, a highly selective double carbonylation reaction at the C-7 was performed resulting in the formation of the corresponding indol-7-ylglyoxylamides when monoamines were used. The bromoarene moiety remained intact, so bromo-substituted glyoxylamides of practical importance have been synthesised in moderate to high yields. The use of chiral alkyl and aryl diamines as nucheophiles allowed the synthesis of a new family of dimeric 7-indole derivatives under moderate reaction conditions (10 bar, 100 °C). The aminocarbonylation at the C-5 position led to much lower chemoselectivities toward indol-5-ylglyoxylamides under similar conditions (40 bar CO, 50 °C). The aminocarbonylation of iodoindoles shows a strikingly different chemoselectivity depending on the basicity of the amine while primary and secondary amines of high basicity gave 2-ketocarboxamides in up to 98% chemoselectivity, aniline resulted in almost exclusive formation of the corresponding carboxamide product. [ABSTRACT FROM AUTHOR]

Abstract: 5-Iodo- and 4,5-dibromo-2-methylpyridazin-3(2H)-ones were aminocarbonylated in the presence of various amines including amino acid methyl esters in a palladium-catalysed reaction. The iodo derivative afforded the corresponding amides with complete conversion and high isolated yields. The dibromo derivative has shown unexpectedly high reactivity in this reaction, resulting in 4,5-dicarboxamides using primary amines as N-nucleophiles. Monoaminocarbonylation has not been observed, i.e., neither 4-bromo-5-carboxamide nor 4-carboxamido-5-bromo derivatives have been formed. However, the use of secondary amines such as piperidine and morpholine resulted in the formations of mixtures of amino-substituted bromopyridazinones. That is, no carbon monoxide insertion took place in these cases. Some mechanistic details of the formation of aminocarbonylation and amination products are also discussed. [Copyright &y& Elsevier]

Abstract: Various 5-carboxamido-7-iodo-8-benzyloxyquinolines were synthesised via selective aminocarbonylation of 5,7-diiodo-8-benzyloxyquinoline in the presence of ‘in situ’ generated palladium(0) catalysts. Under similar conditions (50 °C, 80 bar CO), 5,7-bis(N-tert-butyl-glyoxylamido)-8-hydroxyquinoline was obtained using tert-butylamine as N-nucleophile. The unprotected 5,7-diiodo-8-hydroxyquinoline underwent dehydroiodination resulting in 8-hydroxyquinoline as the major product. [Copyright &y& Elsevier]

Abstract: 1-Isoindolinone derivatives were synthesised in high yields (up to 89%) by using 2-iodobenzyl bromide and 2-iodobenzylamine as bifunctional substrates in palladium-catalysed carbonylation. Depending on the N-nucleophiles, two types of compounds were synthesised with 2-iodobenzyl bromide: the use of primary amines, including amino acid methylesters, resulted in the formation of N-substituted 1-isoindolinones, while secondary amines react both with the benzyl bromide and iodoarene moieties resulting in the corresponding ortho-(N-piperidino/morpholinomethyl)-benzamides. The parent 1-isoindolinone was obtained in a facile, highly chemoselective intramolecular aminocarbonylation of 2-iodobenzylamine. The mechanistic details of the ring-closure reaction and the conditions leading to side-products are discussed as well. [ABSTRACT FROM AUTHOR]

Abstract: 3,17-Dicarboxamido-androst-3,5,16-triene, 3-carboxamido-androst-3,5-dien-17-one, 17-carboxamido-androst-4,16-dien-3-one and 11-carboxamido-androst-5,9(11)-dien-3,17-dione derivatives were synthesized in homogeneous carbonylation reactions from the corresponding 3,17-diiodo-androst-3,5,16-triene, 3-iodo-androst-3,5-diene-17-ethylene ketal, 17-iodo-androst-5,16-dien-3-ethylene ketal, 11-iodo-androst-5,9(11)-diene-3,17-bis(ethylene ketal) derivatives, respectively. A highly chemoselective palladium-catalyzed aminocarbonylation of the corresponding iodo-alkene, carried out under mild reaction conditions, can be considered as the key-step for the introduction of the carboxamide functionalities. The synthesis of the iodo-alkene substrate is based on the transformation of the corresponding keto derivative to hydrazone, which was treated with iodine in the presence of a base (1,1,3,3-tetramethyl guanidine). The aminocarbonylation reaction is highly tolerant towards the N-nucleophiles, i.e. various primary and secondary amines including amino acid methyl esters can also be used. [ABSTRACT FROM AUTHOR]

Abstract: 17a-Methoxycarbonyl- and 17a-carboxamido-d-homoestra-1,3,5(10),17-tetraene derivatives were synthesized by palladium-catalyzed carbonylation reactions of the corresponding 17a-iodo-d-homoestra-1,3,5(10),17-tetraene derivatives using methanol and various amines as O- and N-nucleophiles, respectively. Both the natural (13β) and the epi (13α) series of compounds were isolated. The 17a-iodo-17-ene functionalities in the two 13-epimer series differ in reactivity. While the aminocarbonylations were practically complete in the 13β series in reasonable reaction time under mild conditions and high isolated yields were achieved, the corresponding 13α-17a-iodo-17-ene substrate has shown decreased reactivity resulting in moderate to low yields. However, under high carbon monoxide pressure (40 bar) excellent yields can be obtained even in the 13α series. The aminocarbonylation was completely chemoselective in both series, i.e., the corresponding 17a-carboxamido-17-ene derivatives were formed exclusively. [ABSTRACT FROM AUTHOR]

Abstract: Iodoarenes (iodobenzene and 2-iodothiophene) and iodoalkenes (1-iodocyclohexene, 1-iodo-4-tert-butylcyclohexene, 1-iodo-2-methylcyclohexene and 1-iodo-1-(1-naphthyl)ethene) were used as substrates in palladium-catalysed aminocarbonylation with N,O-dimethylhydroxylamine. The corresponding Weinreb amides were prepared in high isolated yields (up to 87%) when forcing conditions (40–60bar of CO, 50°C) were used. The aminocarbonylation provides the Weinreb amides as pure products in a chemoselective reaction. No formation of ketocarboxamides, due to double CO insertion, except for 2-iodothiophene, was observed even at 60bar of CO pressure. [Copyright &y& Elsevier]

Abstract: Two highly reactive iodoalkenes (1-iodo-1-(2-naphthyl)ethene and 1-iodo-1-(1-naphthyl)ethene) were prepared from the corresponding acetonaphthone isomers via their hydrazones and used as substrates in palladium-catalysed carbonylations. Both iodoalkenyl substrates proved to be highly reactive in the presence of various N-nucleophiles and the corresponding N-substituted naphthylacrylamides were formed chemoselectively in nearly quantitative yields. High isolated yields (up to 93%) were achieved with all types of amines under mild reaction conditions. The alkoxycarbonylation of the above iodoalkenes resulted in esters of unexpectedly good isolated yields (up to 77%). [Copyright &y& Elsevier]

Abstract: 17-Alkoxycarbonyl- and 17-carboxamido-3β-hydroxy-13α-androsta-5,16-diene derivatives were synthetized in high yields in the palladium-catalyzed carbonylation reactions of the corresponding 3β-hydroxy-17-iodo-13α-androsta-5,16-diene. This substrate with a 17-iodo-16-ene functionality was obtained from the 17-keto derivative via its 17-hydrazone, which was treated with iodine in the presence of a base (1,1,3,3-tetramethylguanidine). 17-Carboxamides were obtained by chemoselective aminocarbonylation through the use of amines, including amino acid esters, as N-nucleophiles. The 17-methoxycarbonyl-16-ene derivative was synthetized by using methanol as O-nucleophile. The parent compound of this series, the 17-carboxylic acid derivative, was formed in the presence of water via hydroxycarbonylation. [Copyright &y& Elsevier]

Abstract: Various amine nucleophiles including glycine methyl ester were used in the palladium-catalysed aminocarbonylation of (E)- and (Z)-1-iodo-1-dodecene. The substrates were synthesised from 1-dodecanal via the corresponding hydrazone, which was treated with iodine in the presence of tetramethylguanidine. The homogeneous catalytic aminocarbonylation resulted in the corresponding odd-number carboxamides in moderate to good yields. The reaction was accompanied by the formation of some carboxamides with triple bonds in the 2-position. The latter products were formed in relatively high yields with secondary amines such as piperidine and morpholine and were isolated as pure compounds. [Copyright &y& Elsevier]

Abstract: The high-yielding synthesis of novel N-acyl phosphonates with unprecedented structure was carried out by a homogeneous carbonylation reaction under mild reaction conditions. The palladium-catalysed aminocarbonylation of iodoalkenes (1-iodo-cyclohexene, 1-iodo-4-tert-butyl-cyclohexene, 1-iodo-2-methyl-cyclohexene and α-iodostyrene) with diethyl α-aminobenzyl-phosphonate as N-nucleophile resulted in the exclusive formation of carboxamides. The same reaction with iodoaromatics (iodobenzene, 2-iodothiophene) provided the corresponding carboxamide in high yields and some 2-keto-carboxamides as side products due to single and double carbon monoxide insertion, respectively. [Copyright &y& Elsevier]

Abstract: 17-Alkoxycarbonyl- and 17-carboxamido-13α-estra-1,3,5(10),16-tetraenes were synthesized from the 17-iodo-13α-estra-1,3,5(10),16-tetraene derivative in palladium-catalyzed alkoxycarbonylation and aminocarbonylation reactions, respectively. The synthesis of the 17-iodo-16-ene derivative, used as substrate, is based on the transformation of the 17-keto derivative (epiestrone methyl ether) to hydrazone, which was treated with iodine in the presence of a base (1,1,3,3-tetramethyl guanidine). 17-Carboxamides were obtained in good yields (up to 88%) not only with simple alkyl/aryl amines but also with amino acid methyl esters as N-nucleophiles. The use of alcohols as O-nucleophiles in alkoxycarbonylation resulted in the corresponding 17-esters; however, yields of synthetic interest were obtained only with methanol. [Copyright &y& Elsevier]

Abstract: 1,8-Diiodo-naphthalene was aminocarbonylated with various primary and secondary amines in the presence of palladium(0) complexes formed in situ from palladium(II) acetate and triphenylphosphine. In the case of primary amines, depending on the amine to substrate ratio, two types of products have been obtained in highly chemoselective reaction: dicarboxamides and N-substituted imides have been formed at high and low amine to substrate ratio, respectively. The reaction tolerates the ester functionality, so that amino acid esters could serve as N-nucleophiles and in this way, naphthalimides possessing stereogenic centre in the N-substituent could be synthesised. [Copyright &y& Elsevier]

Abstract: Highly reactive iodoalkenes (α-iodostyrene and α,α′-diiodo-1,4-divinylbenzene) were prepared and used as substrates in palladium-catalysed aminocarbonylation reaction. Regardless of the type of amine nucleophile the corresponding N-substituted phenylacrylamides have been formed chemoselectively in nearly quantitative yields. High isolated yields (up to 83%) have been achieved both with unfunctionalised simple amines and amino acid methyl esters under mild reaction conditions. [Copyright &y& Elsevier]

Abstract: Various primary and secondary amines, including amino acid methyl esters, were used as nucleophiles in palladium-catalysed aminocarbonylation of 2-iodopyridine, 3-iodopyridine and iodopyrazine. N-Substituted nicotinamides and 3-pyridyl-glyoxylamides (2-oxo-carboxamide type derivatives) of potential biological importance can be obtained from 3-iodopyridine as a result of simple and double carbon monoxide insertions, respectively. The latter examples can be obtained in synthetically acceptable yields by using elevated carbon monoxide pressure. On the contrary, N-alkyl/aryl-carboxamides were obtained exclusively in the whole pressure range by using 2-iodopyridine and iodopyrazine. [Copyright &y& Elsevier]

Abstract: A systematic investigation of the palladium-catalysed aminocarbonylation of iodobenzene, 1-iodocyclohexene and 1′-iodostyrene in the presence of N-nucleophiles containing pyridyl moieties (2-, 3- and 4-picolylamine, N-ethyl-4-picolylamine, di-(2-picolyl)amine) was carried out. The two types of iodo substrates differ substantially regarding the selectivity towards carbonylation: while the aminocarbonylation of iodobenzene resulted in the formation of carboxamide and ketocarboxamide mixtures under various conditions, with the predominant formation of ketocarboxamide even at low carbon monoxide pressure, the aminocarbonylation of iodoalkenes under same conditions gave the corresponding unsaturated carboxamide exclusively. Most of the carboxamides and phenylglyoxylamides, obtained via single and double carbon monoxide insertion, respectively, were isolated in yields of synthetic interest (up to 86%). Low reaction rates and unexpected chemoselectivity towards carboxamide formation have been observed with di-(2-picolyl)amine as N-nucleophile in the aminocarbonylation of iodobenzene. [Copyright &y& Elsevier]

Highlights: [•] Novel androstane-based 3,17-dicarboxamides were synthesized. [•] Systematic investigation on the synthesis of homo- and mixed diamides was carried out. [•] The products are potential 5α-reductase inhibitors of pharmacological importance. [•] High-yielding aminocarbonylation was used as key-reaction in the multistep synthesis. [Copyright &y& Elsevier]

Abstract: 1-Iodocyclohexene, a benchmark substrate, has been double carbonylated in the presence of palladium-phosphite precatalysts. Triarylphosphites with OR substituents, able to act both as P-monodentate and hemilabile P,O-heterobidentate ligands were used in this reaction. Systematic investigations have revealed that the chemoselectivity towards cyclohexenylglyoxylamides, i.e., the products obtained in aminocarbonylation by the insertion of two carbon monoxide, is strongly influenced by the amine nucleophile, temperature and carbon monoxide pressure. The highest yields of 2-ketocarboxamides were obtained at low temperature (30 °C) and high carbon monoxide pressure (110 bar). However, the structure of the phosphite ligand has practically no effect either on catalytic activity or chemoselectivity. This fact refers to the P-monodentate coordination of the ligands in catalytic intermediates or that palladium nanoparticles are the catalytically active species. [Copyright &y& Elsevier]

Abstract: 1,2,3,4-Tetrahydrophthalazin-1-one and 1,2,3,4-tetrahydrophthalazin-1,4-dione derivatives were synthesised in high (up to 85%) and low yields using 2-iodobenzyl bromide and 1,2-diiodobenzene as bifunctional substrates, respectively. Iodoarenes, carbon monoxide and various hydrazine derivatives as N-nucleophiles were used in a three-component palladium-catalysed cascade hydrazinocarbonylation. A similar palladium-catalysed reaction, the aminocarbonylation of 1,2-diiodobenzene, resulted mainly in the formation of two types of major products depending on the amine N-nucleophiles: the use of primary amines yielded N-substituted phthalimides in double carbonylation, while secondary amines react with one of the iodoarene functionalities affording the corresponding 2-iodobenzamides. Due to double carbon monoxide insertion at one or both iodoarene functionalities, ketocarboxamide-carboxamide or bis-ketocarboxamide derivatives could be isolated by the modification of the reaction conditions. Some mechanistic details of the ring-closure reactions and the conditions leading to side-products are also discussed. [Copyright &y& Elsevier]

Abstract: 11-Carboxamido-androst-4,9(11)-dienes were synthesized from the corresponding 11-iodo-androst-4,9(11)-diene derivative in palladium-catalyzed aminocarbonylation reaction under mild reaction conditions. The synthesis of the iodo-alkene substrate is based on the transformation of the 11-keto derivative to hydrazone, which was treated with iodine in the presence of a base (1,1,3,3-tetramethyl guanidine). The 11-carboxamides were synthesized in moderate to high isolated yields by using simple alkyl/arylamines or amino acid methylesters as N-nucleophiles. The highly active palladium catalysts enable the homogeneous catalytic functionalization at one of the most hindered position (C-11) of the steroidal skeleton. [Copyright &y& Elsevier]

Iodouracil derivatives (5-iodouracil, 5-iodo-1,3-dimethyluracil) were aminocarbonylated using a set of primary and secondary amines in the presence of in situ palladium(0) catalysts. The formation of carboxamides via single CO insertion was favoured at atmospheric CO pressure. The chemoselectivity toward double CO insertion can be increased by using 40 bar of CO pressure, in this way up to 60% selectivity toward 2-ketocarboxamide was achieved. In the case of 5-iodouracil the corresponding 5-glyoxylamido-uracil derivatives were exclusively formed at 40 bar CO pressure. The only exception is the less basic aniline nucleophile which provided the corresponding carboxamide exclusively. A typical side-reaction took place when 5-iodouracil was used as substrate: this heterocycle, existing in lactam-lactim tautomeric forms, underwent deiodination providing the parent uracil as side-product. Image 1 • Functionalisation of the uracil ring via palladium-catalysed aminocarbonylation. • Selective synthesis of 5-glyoxylamidouracil derivatives at high CO pressure. • Describing a proposed mechanism of deiodination side reaction. • Synthesis of uracil derivatives bearing amide moiety with biological importance. [ABSTRACT FROM AUTHOR]

Alterations in traditional land use practices have led to severe declines in the area of semi-natural grasslands, thereby seriously threatening plant and animal species dependent on these habitats. Small anthropogenic managed habitats, like roadsides can act as refuges and might play an important role in conserving these species. Colonization of roadside verges by endangered lizard orchids ( Himantoglossum spp.) has long been known, but few studies have systematically explored the suitability of roadside habitats for these orchids and the impact of roads on them. In this paper we present results of targeted surveys of three lizard orchid taxa on roadsides from eight European countries. During these surveys we searched for lizard orchids inhabiting roadside verges and recorded their distance from road, aspects of the roadside environment, as well as vegetative and reproductive characteristics of individual plants. We found large numbers of lizard orchids on roadside verges. Distance from roads was not uniformly distributed: orchids occurred more closely to roads than expected by chance. This suggests that regular management of roadsides (e.g. mowing) might enhance colonization and survival of lizard orchids. On the other hand, we also found that close proximity to roads negatively affects reproductive success, suggesting that the immediate vicinity of roads might act as an ecological trap (i.e. favorable in terms of colonization and survival but unfavorable in terms of reproduction). Nonetheless, the fact that significant and viable populations are maintained at roadsides suggests that traditionally managed roadside verges may allow long-term persistence of lizard orchid populations and may serve as refuges in a landscape context. [ABSTRACT FROM AUTHOR]

Abstract: 1-Iodo-3,4-dihydronaphthalene, an iodoalkene substrate obtained from α-tetralon, has been carbonylated in the presence of palladium–phosphine precatalysts. Systematic investigations have revealed that the 1-carboxamido-3,4-dihydronaphthalenes and 1-methoxycarbonyl-3,4-dihydronaphthalene have been formed in exceptionally high isolated yields (up to 96%) in chemospecific reaction. The influence of the amine nucleophile and that of the reaction conditions (carbon monoxide pressure, reaction temperature) on the reactivity of the substrate have been investigated. [Copyright &y& Elsevier]

Abstract: A set of new steroid dimers linked through ring D–ring D were synthesized via catalytic diaminocarbonylation of 17-iodo-5α-androst-16-ene, in the presence of palladium–phosphine in situ catalysts and aliphatic or aromatic diamines as N-nucleophiles. The dimeric steroidal compounds containing 17,17′-dicarboxamide spacers were obtained through highly chemoselective reactions in good isolated yields and completely characterized by spectroscopic techniques. [Copyright &y& Elsevier]

• In situ morphometric data support molecular data in showing that H. adriaticum is a genuine species distinct from H. hircinum. • This species typically forms small populations in open forests, though larger populations can develop in secondary habitats. • The average life span is 8 years and 10% of plants live for at least 15 years. • Flowering threshold is four leaves totalling 50 cm2; populations have flowering frequencies of 4–34% and dormancies of 2–12%. • Fruit set is generally low, increasing with increased inflorescence length and decreasing with shading by woody species. Himantoglossum adriaticum H. Baumann is a long-lived perennial orchid with an adriato-mediterranean distribution. The species-level separation of this species from the more geographically widespread H. hircinum has only recently been confirmed via a combination of molecular and morphometric techniques, which are further developed here. To provide a comprehensive overview of its autecology we integrated previously published information with extensive unpublished data derived mainly from populations in the Keszthely Hills of Hungary. In this paper we assess the distribution, habitat preferences, life history and seed germination (ex situ and in situ) of H. adriaticum , with special emphasis on its reproductive biology. [ABSTRACT FROM AUTHOR]