[reaction: see text] This Mg-TiCl4-promoted CH2-transfer reaction of CH2Cl2 represents an extremely simple, practical, and efficient methylenation of a variety of ketones and aldehydes, especially in enolizable or sterically hindered ketones such as 2,2-dimethylcyclohexanone, camphor, and fenchone.
The Leuckartreaction of 2-norbornanone and (1R)-N-(3,3-dimethyl-2-oxo-1-norbornyl)acetamide ent-1b furnishes the expected N-(2-norbornyl)formamides 11 and ent-10 in good yield. Surprisingly, under the same reaction conditions, the (1R)-N-(7,7-dimethyl-2-oxo-1-norbornyl)acetamide 1a gives only 10, the enantiomeric form of the product obtained from ent-1b. An explanation of these results is given and
Synthesis of homochiral cyclopentane derivatives by Beckmann fragmentation of 1-substituted 2-norbornanones
作者:A.García Martínez、E.Teso Vilar、A. García Fraile、S. de la Moya Cerero、C.Díaz Oliva、L.R. Subramanian、C. Maichle
DOI:10.1016/s0957-4166(00)86247-3
日期:1994.5
The fragmentation of 2-norbornanone oximes 2 was achieved by reaction with Tf2O/pyridine under mild reaction conditions, yielding homochiral (or racemic) cyclopentane derivativel.
通过在温和的反应条件下与Tf 2 O /吡啶反应,可以实现2-降冰片烷酮肟2的断裂,从而生成高手性(或外消旋)的环戊烷衍生物。