SYNTHESIS AND STRUCTURE OF 1-METHYL-5-t-BUTYL-I-AZA-5-PHOSPHACYCLOOCTANE AND ITS PHOSPHINE SULFIDE

Abstract

The eight-membered phosphorus heterocycles Bu^tP(CH₂CH₂CH₂)₂NMe 1 and Bu^t(S)P(CH₂CH₂CH₂)₂NMe 2 have been synthesized by the reaction of Bu^tPC1₂ with the difunctional Grignard reagent MeN(CH₂CH₂CH₂MgCl)₂ and subsequent treatment with elemental sulfur. 2 crystallizes in the monoclinic space group P2₁/c with the unit cell dimensions a 17.728(5), b 6.674(2),c 11.770(2) Å, β 98.12(2)°, Z = 4. The structure was refined to a final R value of 0.047 for 1761 observed reflections. 2 adopts a twist-boat-chair (TBC) conformation. There is no intramolecular P … N interaction but an unusual intermolecular P[dbnd]S … H contact of 2.854 Å.

Key Words:

• Eight-membered phosphorus heterocycle
• phosphine sulfide
• X-ray structure.