Dibromomethane as one-carbon source in organic synthesis: a versatile methodology to prepare the cyclic and acyclic α-methylene or α-keto acid derivatives from the corresponding terminal alkenes
作者:Yung-Son Hon、Yu-Wei Liu、Cheng-Han Hsieh
DOI:10.1016/j.tet.2004.04.013
日期:2004.5
Ozonolysis of mono-substituted alkenes A-1 followed by reacting with a preheated mixture of CH2Br2–Et2NH affords α-substituted acroleins A-2 in good yields. Under very mild reaction conditions, these α-substituted acroleins A-2 can be easily converted to α-methylene esters A-4, which could be further converted to the corresponding α-keto esters A-5. This methodology can be also applied to the preparation
A RhIII‐catalyzed intramolecularoxidative cross‐coupling between double bonds for the synthesis of macrolides is described. Under the optimized reaction conditions, macrocycles containing a diene moiety can be formed in reasonable yields and with excellent chemo‐ and stereoselectivity. This method provides an efficient approach to synthesize macrocyclic compounds containing a 1,3‐conjugated diene
An efficient and versatile method for the preparation of α-keto acid derivatives from terminal alkenes
作者:Yung-Son Hon、Wei-Chih Lin
DOI:10.1016/0040-4039(95)01638-x
日期:1995.10
Ozonolysis of terminal alkenes followed by reacting with a preheated mixture of CH2Br2-Et2NH affords α-substituted acroleins, which can be converted to α-keto acid derivatives in three steps, under very mild reaction conditions.