A Rh-catalyzed chelation-assisted C6-selective C–Hactivation/alkylation of 2-pyridones with readily available alkyl carboxylic acids or anhydrides is introduced. The reaction proceeds via substrate decarbonylation. This approach merges C–H functionalization with readily available anhydrides, allowing for the efficient synthesis of various C6-alkylated 2-pyridones with good functional group tolerance
[EN] PROCESS FOR THE SYNTHESIS OF (5a,17ß)-N-[(2,5-BIS(TRIFLUOROMETHYL)-PHENYL]-3-OXO-4-AZA-5-ANDROST-1-ENE-17-CARBOXAMIDE<br/>[FR] PROCÉDÉ DE SYNTHÈSE DU (5?,17?)-N-[(2,5-BIS(TRIFLUOROMÉTHYL)-PHÉNYL]-3-OXO-4-AZA-5-ANDROST-1-ÈNE-17-CARBOXAMIDE
申请人:RICHTER GEDEON NYRT
公开号:WO2013001322A1
公开(公告)日:2013-01-03
The synthesis consists of reaction steps as follows: oxidizing the α,β-unsaturated ketone system of ring "A" of pregn-4-ene-3,20-dion- of formula (II) with sodium metaperiodate in tert-butanol in the presence of potassium permanganate and alkali metal carbonate, reacting the obtained 3,5-seco acid with an ester of chloroformic acid in the presence of tertier organic base below 0°C, reacting the obtained new compound after isolation or without isolation with ammonia or ammonium acetate, cyclization of the resulting carboxamides with an acid, cathalytic hydrogenating the obtained ene lactame, and oxidizing the side chain at position 17 of the obtained pregnane compound with an alkali metal hypobromide in aqueous dioxane below 10°C. Thereafter on one hand the obtained (5α,17β)-3-oxo-4-aza-5-androstane-17-carboxylic acid is reacted with chloroformic acid ester, the obtained new compound is reacted with 2,5-bis(trifluoromethyl)-aniline in the presence of a Lewis acid, the obtained amide is reacted with trimethyl chlorosilane in inert atmosphere in the presence of Ν,Ν,Ν',Ν'-tetramethyl-ethylendiamine, then en excess iodine is added to the reaction mixture and the product of the iodination reaction is crystallized from acetonitrile, then the obtained 2-iodo-3-oxo-4-aza-17β-carboxamide is reacted with potassium tert-butylate to furnish final product. On the other hand, (5α,17β)-3-oxo-4-aza-5-androstane-17-carboxylic acid is transformed into methylester by known method, this latter is transformed into methyl (2α,5α,17β)-2-iodo-3-oxo-4-aza-5-androstane-17-carboxylate according to known method, the obtained compound is reacted with potassium-tert-butylate, the obtained (5α,17β)-3-oxo-4-aza-5-androst-1-ene-17-carboxylic acid is reacted with an ester of chloroformic acid, then the obtained new compound is coupled with 2,5-bis(trifluoromethyl)-aniline in the presence of a Lewis acid catalyst to gain final product.
A General Amino Acid Synthesis Enabled by Innate Radical Cross-Coupling
作者:Shengyang Ni、Alberto F. Garrido-Castro、Rohan R. Merchant、Justine N. de Gruyter、Daniel C. Schmitt、James J. Mousseau、Gary M. Gallego、Shouliang Yang、Michael R. Collins、Jennifer X. Qiao、Kap-Sun Yeung、David R. Langley、Michael A. Poss、Paul M. Scola、Tian Qin、Phil S. Baran
DOI:10.1002/anie.201809310
日期:2018.10.26
The direct union of primary, secondary, and tertiary carboxylicacids with a chiral glyoxylate‐derived sulfinimine provides rapid access into a variety of enantiomerically pure α‐amino acids (>85 examples). Characterized by operational simplicity, this radical‐basedreaction enables the modular assembly of exotic α‐amino acids, including both unprecedented structures and those of established industrial
Cycloalkylation of C(sp<sup>3</sup>)-H Bond with Neighboring Carboxylic Acid as Traceless Activating Group
作者:Leiyang Lv、Zhiping Li
DOI:10.1021/acs.joc.6b03091
日期:2017.3.3
cycloalkylation is developed with neighboring carboxylic acid as a traceless activating group. Primary and secondary alkyl carboxylic acids undergo decarboxylation/α-C(sp3)-H cleavage/cycloalkylation to give the five-membered cyclization products, while tertiary acids undergo decarboxylation/β-C(sp3)-H cleavage/cycloalkylation to generate the six-membered cyclization products.
Thioether-directed Rh(<scp>iii</scp>)-catalyzed <i>peri</i>-selective acyloxylation of arenes
作者:Hui Xie、Jia-Lin Song、Chun-Yong Jiang、Yan-Xia Huang、Jun-Yi Zeng、Xu-Ge Liu、Shang-Shi Zhang、Fan Yang
DOI:10.1039/d1ob02236a
日期:——
A thioether directed acyloxylation of arenes has been realized via Cp*Rh(III)-catalyzed C–H activation and subsequent coupling with carboxylic acids. This new method showed high functional group compatibility and broad substrate scope. Primary mechanistic studies have been conducted and a tentative reaction mechanism was proposed. It represents the first example of a thioether-directed Cp*Rh(III)-catalyzed
通过Cp*Rh( III ) 催化的 C-H 活化和随后与羧酸的偶联,实现了芳烃的硫醚定向酰氧基化。这种新方法显示出高官能团相容性和广泛的底物范围。已经进行了初步的机理研究,并提出了初步的反应机理。它代表了硫醚指导的 Cp*Rh( III ) 催化的 C(sp 2 )-H 酰氧基化反应的第一个例子。