1,3,2,4-Diselenastannaboretane, a novel selenium-containing four-membered boracycle: synthesis, structure and thermal cycloreversion into a selenoxoborane

Abstract

Treatment of an overcrowded aryl trihydroborate bearing 2,4,6-tris[bis(trimethylsilyl)methyl]phenyl (Tbt) group with Cp₂TiSe₅ followed by the addition of Ar₂SnCl₂ (Ar = Ph or Mes) and Ph₃P resulted in the isolation of novel selenium-containing four-membered boracycles, 1,3,2,4-diselenastannaboretanes, the thermolysis of which in the presence of 2,3-dimethyl-1,3-butadiene or 2,4,6-tri-tert-butylbenzonitrile oxide indicated the formation of a novel class of boron-containing doubly bonded compound, an arylselenoxoborane (Tbt)B[double bond, length half m-dash]Se.

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