Synthesis and Double Olefin Extrusion of 2,2,6,6-Tetraaryl-l,5-Dioxa-4λ⁵- Phosphaspiro[3.3]Heptanes

Abstract

The title compounds were synthesized by cyclization and dehydration of the corresponding bis(β-hydroxyalkyl)phosphine oxides with Appel's reagent. Since these compounds were very moisture sensitive to hydrolyze to the starting bis(β-hydroxyalkyl)phosphine oxides except for tetrakis(4-nitrophenyl) derivative, their in-situ generation and thermolysis were carried out to give two molar equivalents of the corresponding olefins in good yield in sharp contrast to tetrakis(tri-fluoromethyl) derivative.

Keywords::

• Pentacoordinate 1,2-oxaphosphetanes
• Wittig reaction
• Thermolysis
• Double olefin extrusion
• l,5-Dioxa-4λ⁵-spiro[3.3]-heptanes