Reaktivität des labilen, durch Adduktbildung mit Ph2C=NSiMe3 gespeicherten Silaethens Me2Si=C(SiMe3)2 / Reactivity of the Labile Silaethene Me2Si = C(SiMe3)2, Stored as Ph2C =NSiMe3 Adducts

Abstract

Silaethene Me2Si = C(SiMe3)2 (1), stored as Ph2C=NSiMe3 adducts and regenerated from the adducts at about 100 °C as a reaction intermediate, combines with reactants a-b (e. g. HO-H, RO-H. RCOO-H, RS-H. RHN-H, Ph2CN-H, RO-SiR3, R2N-SiR3, Ph2CN-SiR3, Cl-GeR3, Cl-SnR3) with insertion into the a-b bond, with a=b (e.g. 0 = CPh2, Me3SiN = CPh2, CH2=CHOMe, cis-piperylene), a=b=c (e.g. RN = N = N, O = N=N). a=b-c=d (e.g. butadiene, isoprene, trans-piperylene, 2,3-dimethylbutadiene, cyclopentadiene, anthracene, benzophenone, N-trimethylsilylbenzophenoneimine) under [2+2]-, [2+3]- as well as [2+A]-cycloaddition and with a=b-c-H (e.g. propene, butenes, isoprene. 2.3-dimethylbutadiene, acetone) under ene reac­tion. According to relative reaction rates, insertion and [2+2]-cycloadditions seem to proceed in two reaction steps, whereas [2+4]-cycloadditions and ene reactions with organic dienes and enes obviously are one step reactions. For relative reactivities cf. Table I.