The crystal and molecular structure of a cyclic phosphite–borane adduct

Abstract

The structure of 2-methoxy-cis-4,6-dimethyl-1,3,2-dioxaphosphorinan–borane has been determined by three-dimensional single-crystal X-ray analysis. The compound is orthorhombic, space group P2₁2₁2₁, with a= 9·68 ± 0·03, b= 14·13 ± 0·05, c= 7·51 ± 0·03 Å, and Z= 4. The ring exists in a chair conformation, with an axial 2-methoxy group and two equatorial methyl groups. The mean P–O bond length is 1·562 Å; C–C distances range from 1·48 to 1·55 Å, and C–O distances from 1·47 to 1·51 Å. The structural results are compared with those for related phosphates.