Catalytic Enantioselective Michael Addition of α-Aryl-α-Isocyanoacetates to Vinyl Selenone: Synthesis of α,α-Disubstituted α-Amino Acids and (+)- and (−)-Trigonoliimine A
作者:Thomas Buyck、Qian Wang、Jieping Zhu
DOI:10.1002/anie.201306663
日期:2013.11.25
title reaction in the presence of the catalyst 1 afforded Michael adducts in excellent yields and enantioselectivities. The adducts were readily converted into α,α′‐disubstituted α‐aminoacids. The enantioselective total synthesis of both (+)‐ and (−)‐trigonoliimine A was accomplished using one of the Michael adducts derived from this methodology. M.S.=molecular sieves.
Silver-Catalyzed Asymmetric Desymmetrization of Cyclopentenediones via [3 + 2] Cycloaddition with α-Substituted Isocyanoacetates
作者:Jimil George、Hun Young Kim、Kyungsoo Oh
DOI:10.1021/acs.orglett.8b00590
日期:2018.4.20
A highly selective and practical asymmetric Ag(I) catalyst system has been developed for the [3 + 2] cycloaddition reactions between isocyanoacetates and cyclopentenediones. The current Ag(I) catalyst system tolerates moisture and air and readily utilizes class III solvents such as EtOAc and acetone. The development of on demand generation of an active chiral catalyst in the presence of isocyanides
Palladium-Catalyzed Nucleophilic Isocyanation for the Synthesis of α-Aryl-α-Isocyanoacetoamide Derivatives
作者:Taiga Yurino、Yuji Tange、Takeshi Ohkuma
DOI:10.1246/bcsj.20210214
日期:2021.9.15
mandelamide derivatives reacted with trimethylsilylcyanide in the presence of a catalytic amount of Pd(OAC)2 to afford the titled isonitriles (13 examples) in moderate to high yield. The silyl cyanopalladate complex formed in situ was a proposed catalyst, which behaved as a Lewisacidpromoting elimination of the phosphate group and also the N-nucleophilic cyanide reagent. The isocyanation was applied
Construction of Optically Active 2<i>H</i>‐ and 3<i>H</i>‐Pyrroles by Cyclization and Chirality Maintaining<i>1,5</i>‐Ester Shift Reactions
作者:Dan Li、Linqing Wang、Yuling Yang、Minmin Zhang、Tianyu Peng、Dongxu Yang、Rui Wang
DOI:10.1002/adsc.201900481
日期:2019.8.21
realize the asymmetric synthesis of 2H‐pyrroles, a proper in situ generated magnesium catalytic method was developed. On the other hand, the discovery of an aluminium mediated chirality maintaining 1,5‐ester shift reaction promoted the successful synthesis of enantioenriched 3H‐pyrroles.
Metal‐free Decarboxylative Annulation of 2‐Aryl‐2‐isocyano‐acetates with Aryldiazonium Salts: General Access to 1,3‐Diaryl‐1,2,4‐triazoles
作者:Yu‐Ting Tian、Fa‐Guang Zhang、Jing Nie、Chi Wai Cheung、Jun‐An Ma
DOI:10.1002/adsc.202001016
日期:2021.1.5
Isocyanoacetates are versatile substrates for the synthesis of heterocyclic compounds, but the concomitant decarboxylation remains rare. Herein we report a decarboxylative annulation reaction of 2‐aryl‐2‐isocyanoacetates with aryldiazonium salts. This metal‐free, base‐promoted protocol allows for the access to a broad collection of 1,3‐diaryl‐1,2,4‐triazoles, including chiral triazole‐based binaphthalene