Organocatalyzed Asymmetric Conjugate Addition of Heteroaryl and Aryl Trifluoroborates: a Synthetic Strategy for Discoipyrrole D
作者:Jiun‐Le Shih、Thien S. Nguyen、Jeremy A. May
DOI:10.1002/anie.201503528
日期:2015.8.17
Bis‐heteroaryl or bis‐aryl stereocenters were formed by an organocatalytic enantioselective conjugateaddition using the respective trifluoroborate salts as nucleophiles. Control studies suggested that fluoride dissociation is necessary in the anhydrous conditions. This strategy is applicable to the synthesis of discoipyrroleD, an inhibitor of BR5 fibroblast migration.
Synthesis of Unsaturated Organotrifluoroborates via Wittig and Horner−Wadsworth−Emmons Olefination
作者:Gary A. Molander、Ruth Figueroa
DOI:10.1021/jo060863w
日期:2006.8.1
stereoselective synthesis of unsaturated organotrifluoroborates by using the Wittig and Horner−Wadsworth−Emmons olefination is described. These reactions were general for both alkyl- and aryltrifluoroborates. The synthesis of di- and trisubstituted olefins was achieved by using formyl- and acetyl-substituted organotrifluoroborates. The products were isolated in moderate to excellent yield. The Wittig reaction
Oxidative Condensations To Form Benzimidazole-Substituted Potassium Organotrifluoroborates
作者:Gary A. Molander、Kehinde Ajayi
DOI:10.1021/ol301956p
日期:2012.8.17
benzimidazole-substituted potassium organotrifluoroborates was prepared via the condensation of various potassium formyl-substituted aryl- and heteroaryltrifluoroborates with aromatic 1,2-diamines under oxidative conditions. The efficient Suzuki–Miyaura cross-coupling of products thus formed to various aryl and heteroaryl bromides was achieved in good yields. The method allows the facile preparation of benzimidazole-containing
Organocatalytic Vinyl and Friedel−Crafts Alkylations with Trifluoroborate Salts
作者:Sandra Lee、David W. C. MacMillan
DOI:10.1021/ja0767480
日期:2007.12.1
pathway. Boronic acids can also be employed as viable π-nucleophiles for these asymmetric conjugate additions provided that in situ activation to the corresponding boronate species is accomplished. While BF3K salts are routinely employed in transition metal catalysis, to our knowledge, this is the first use of this activation group for organic catalysis or Friedel−Crafts alkylations.
A metal‐free cis‐diastereoselective coupling between thymidine 5,6‐epoxides and various aryl‐ and alkynyltrifluoroborates followed by a nearly quantitative dehydration step provided C‐6‐substitued aryl and alkynyl thymidines in high overall yields.