Silyl-nitrogen compounds ⁺ : Part VIII - Reactions of pentasilaphospha- pentazene with some group (V) derivatives

Abstract

Pentakis(trimethylsilyl)-3-phospha-2-pentazene, (Me₃Si)₂N-N (SiMe₃)-P=N-N(SiMe₃)₂ (1) reacts with POCI₃ to form a [2+2]-cycloadduct, 2,2,2-trichloro-3-bis(tri-methylsilyl)amino-4-tris (trimethylsilyl) hydrazino- 1 -oxa- 3-amino-2,4-diphosphacyclobutane (2) which loses trimethylchlorosilane to form 2,5-dichloro-5-oxo-3, 4- bis(trimethylsilyl)-2-bis(trimethylsilyl) amino-1,3,4-triaza-2, 5-diphosphacyclopent- 1 -ene, (3). With ECI₃(E=P or As), (1) forms partially desilylated heterocycle, 2,5-dichloro-3.4-bis(trimethylsilyl)-1 ,2.4-triaza-2-phospha-3- (phospha or arsa)-cyclopentane, (4,5). However, AsBr₃, forms 5-bromo-4-trimethylsilyl-1-bis (trimethylsilyl) amino-1,3,4-triaza-2-phospha-5-arsa-cycIopent-2-ene (6) which loses Me₃SiBr to provide 1-bis (trimethylsilyl)amino-1,3.4-triaza-2-phospha-5-arsa-cyclopent-2,4-diene, (7).