Crystal structure of 2-chloro-1,3-bis­­(2,6-diiso­propyl­phen­yl)-1,3,2-di­aza­phospho­lidine 2-oxide

The title compound, C26H38ClN2OP, was synthesized by reacting phosphoryl chloride with N,N′-bis­(2,6-diiso­propyl­phen­yl)ethane-1,2-di­amine in the presence of N-methyl­morpholine which acted as an auxilliary base to quench the HCl released as a by-product. The resultant N-heterocyclic phosphine five-membered ring adopts a half-chair conformation and features a tetra­coordinate P atom ligated by the chelating di­amine [P—N = 1.6348 (14) and 1.6192 (14) Å], one double-bonded O atom [P1—O1 = 1.4652 (12) Å] and one Cl atom [P1—Cl1 = 2.0592 (7) Å]. The sterically hindered 2,6-diiso­propyl­phenyl (Dipp) groups twist away from the central heterocycle, with torsion angles of −75.66 (19) and 83.39 (19)° for the P—N—Car—Car links. A number of intra­molecular C—H⋯N, C—H⋯O and C—H⋯Cl close contacts occur. In the crystal, mol­ecules are linked by C—H⋯O hydrogen bonds to generate [010] chains. C—H⋯π inter­actions are also observed.