Synthesis of 2-lithio-1,3-diselenanes and 2-lithio-1,3-dithianes by Se/Li exchange: First successful trapping of axially oriented 2-lithio-1,3-diselenanes
作者:Alain Krief、Laurent Defrère
DOI:10.1016/0040-4039(96)01813-8
日期:1996.10
2-methylseleno-1,3-diselenanes bearing the methylseleno moiety in axial position react with butyllithiums at low temperature (−130°C) to produce 2-lithio-1,3-diselenanes bearing the lithium in axial position. These organometallics are configurationally stable at −130°C and slowly epimerise at −78°C. Deuteration occurs exclusively from the axial side if carried out at −130°C. 2-Methylseleno-1,3-dithianes