Reductive Alkylation of Tertiary Lactams via Addition of Organocopper (RCu) Reagents to Thioiminium Ions
作者:Pierre Mateo、Joséphine E. Cinqualbre、Melinda Meyer Mojzes、Kurt Schenk、Philippe Renaud
DOI:10.1021/acs.joc.7b02150
日期:2017.12.1
A simple procedure for the conversion of tertiary lactams to 2-monoalkylated cyclic amines is described. The reaction sequence involves conversion of a lactam to a thioiminium ion followed by reaction with an organocopper (RCu) reagent and final reduction with triacetoxyborohydride. The reaction is high yielding and shows an excellent functional group tolerance. Its utility is demonstrated by a rapid
Carbocupration/Zinc Carbenoid Homologation and β-Elimination Reactions for a New Synthesis of Allenes − Application to the Enantioselective Synthesis of Chiral Allenes by Deracemization of sp3-Organometallic Derivatives
作者:Jos P. Varghese、Irena Zouev、Lionel Aufauvre、Paul Knochel、Ilan Marek
straightforward carbocupration/zinc homologation/β-elimination reaction sequence allows the one-pot synthesis of polysubstituted allenes from acetylenic sulfoxides in excellent isolated chemical yields. Secondary zinccarbenoids were used for the homologation reaction, and so a new synthesis of 1,1-diiodoalkanes is described. This methodology also allows the synthesis of chiral allenes through thermodynamic
We describe a powerful, broadly applicable cross-coupling protocol that enables carbon–carbon bondformation at highly sterically hindered carbon centers (both sp2 and sp3) by employing organocopper reagents under palladium catalysis. Experimental studies and theoretical calculations indicated that the key to the unique reactivity of copper is the relatively low activation energy of the compact transmetalation
Synthesis and rotational barriers of atropisomers of 1,2-bis[5-(11H-benzo[b]fluorenyl)]benzenes and related compounds
作者:Hua Yang、Jeffrey L. Petersen、Kung K. Wang
DOI:10.1016/j.tet.2005.10.062
日期:2006.2
Several 1,2-bis[5-(11H-benzo[b]fluorenyl)]benzenes and relatedcompounds were synthesized via a cascade reaction sequence of the corresponding benzannulated enyne-allene precursors. The X-ray structures showed that the two benzo[b]fluorenyl moieties attached via the C5 carbons to the adjacent carbon atoms of the central benzene ring are oriented essentially perpendicular to the central benzene ring.
通过相应的苯并环化的烯炔-丙二烯前体的级联反应序列,合成了一些1,2-双[5-(11 H-苯并[ b ]芴基)]苯和相关化合物。X射线结构表明,经由C 5碳连接至中心苯环的相邻碳原子的两个苯并[ b ]芴基部分基本上垂直于中心苯环。围绕碳-碳单键附接苯并[旋转速率b ]芴基结构部分至中央苯环相对较慢,允许几个抗和顺式在环境温度下被分离阻转异构体。
New Allene Synthesis via Carbocupration−Zinc Carbenoid Homologation and β-Elimination Sequence
作者:Jos P. Varghese、Paul Knochel、Ilan Marek
DOI:10.1021/ol006276t
日期:2000.9.1
the consecutive carbocupration-homologation-beta-elimination reactions on the easily accessible alkynyl sulfoxides or sulfones. This one-pot reaction also allows the preparation of functionalized allenes.