The behaviour of N-t-butyl-2,2′-iminodiethanol towards some trivalent phosphorus compounds

Abstract

Phosphorus trichloride and hexamethylphosphorus triamide react with N-t-butyl-2,2′-iminodiethanol (4) forming the 2 : 3 adduct N,N-bis[2-(6-t-butyl-1,3,6,2-dioxazaphosphoran-2-yloxy)ethyl-t-butyl-amine (5) which, on treatment with water (2 mol equiv.) is hydrolysed to give 6-t-butyl-1,3,6,2-dioxazaphosphocane 2-oxide (8) and N-t-butyl-2,2′-iminodiethanol (4). Compound (8) reacts with o-chloranil to produce a crystalline product which in solution gives an equilibrium mixture of six-co-ordinated phosphorus with a P–OH bond (9) and the phosphate ester (10). Phenylphosphonous dichloride and N,N,N′,N′-tetramethyl-P-phenylphosphonous diamide react with (4) to give 2-phenyl-6-t-butyl-1,3,6,2-dioxazaphosphocane (11) which adds to o-chloranil to form a tautomeric equilibrium mixture of the four-co-ordinate and six-co-ordinate phosphorus compounds (13)⇌(14). Phenyl azide reacts with (11) to give 2-phenyl-2-phenylimino-6-t-butyl-1,3,6,2-dioxazaphosphocane (15). The structural assignments are based on analytical, chemical, and spectroscopic results.