[Bis(trimethylsilyl)methylen](diisopropylamino)boran: ein Allen‐homologes NBC‐System

Abstract

[Bis(trimethylsilyl) methylene] (diisopropylamino) borane: an Allene‐Type N = B = C System The title compound i Pr 2 NBC(SiMe 3 ) 2 ( 4 ) is formed as a storable colourless liquid by the elimination of FSiMe 3 from F–( i Pr 2 N)B–C(SiMe 3 ) 3 ( 3 ) at 520°C. The compounds OCHPh and Me 3 SiN 3 are added to the BC bond of 4 to give the [2 + 2] cycloaddition product 5 and the [2 + 3] cycloaddition product 6 , respectively. The alkylideneaminoborane 4 crystallizes in the space group P 2 1 / n. Perpendicular planes through C 2 NB and BCSi 2 define an allene‐type structure with a linear NBC skeleton, bond lengths 136.3 (NB) and 139.1 pm (BC).