Beiträge zur Chemie des Phosphors, 124 Tri-tert-butyl-diphosphastiba-cyclopropan, (t-BuP)₂Sb(t-Bu)/Contributions to the Chemistry of Phosphorus, 124 Tri-tert-butyl-diphosphastiba-cyclopropane, (t-BuP)₂Sb(t-Bu)

Abstract

<jats:title>Abstract</jats:title><jats:p> The first three-membered P<jats:sub>2</jats:sub>Sb heterocycle, tri-tert-butyl-diphosphastiba-cyclopropane (tri-tert-butyl-diphosphastibirane) (1) was synthesized by [2+1] cyclocondensation of K(t-Bu)P-P(t-Bu)K with t-BuSbCl<jats:sub>2</jats:sub> in n-pentane at -78 °C. Tetra-tert-butyl-1,2-diphospha- 3,4-distiba-cyclobutane (2), tetra-tert-butyl-triphosphastibacyclobutane (3) as well as (t-BuP)<jats:sub>4</jats:sub> and five-membered cyclostibaphosphanes are also formed. Because of its hyperreactivity, 1 could not be isolated in a pure state. It forms two diastereomers, of which the isomer with trans-oriented tert-butyl groups at the phosphorus atoms is the more stable one. The <jats:sup>31</jats:sup>P NMR parameters of the four-membered cyclostibaphosphanes 2 and 3 are reported.</jats:p>