OrganosubstituierteBicyclen undMonocyclen aus 2,5‐Dihydro‐1,2,5‐oxasilaboratolaten

Organosubstituted Bicyclic and Monocyclic Compounds from 2,5‐Dihydro‐1,2,5‐oxasilaboratolates1a) The potassium salts of the cyclic anions of (A: R, R′ = CH3; B: R = C2H5, R′ = CH3; C: R = C6H5, R′ = CH3 react with [(CH3)2NCH2]Br in THF to yield the bicyclic compounds 1a (X‐ray crystal structure analysis), 1b/1b' (endo/exo‐C2H5), and 1c/1c' (endo/exo‐C6H5). D (RCH3, R'=C6H5) reacts with [(CH)32NCH2]Br to form a 1:4 mixture of 1d together with the heterocycle (3d) with elimination of (CH3)2N‐C3H7. – From A – D and CIP(C6H5)2 the six‐membered heterocycles (2a−d) are obtained in yields of ca. 90%.