PHOSPHORUS-NITROGEN COMPOUNDS. PART 48¹. THE REACTIONS OF N,N-DIMETHYLTOLUIDINES WITH PHOSPHORUS(V) CHLORIDES. FORMATION OF A NOVEL HETEROCYCLIC SYSTEM

Abstract

The reactions of phosphorus oxychloride, P(O)Cl₃, with the three N,N-dimethyltoluidines have been studied. O-toluidine gave after suitable work-up only a “nitrogen-substituted” derivative, P(O)(NMeC₆H₄ Me-2)(OEt)₂, whilst the m-analogue gave both “nitrogen-substituted”; P(O)(NMeC₆H₄Me-3)(OEt)₂, and “carbon-substituted” products, P(O)(C₆H₃Me-2-NMe),₂ (OEt), as well as two purely organic compounds, CH₂(C₆H₃Me-2-NMe₂-4)₂ and CH(C₆H₃Me-2-NMe₂-4)₃. With N,N-dimethyl-p-toluidine in addition to two acyclic ‘nitrogen-substituted’ products, P(O)(NMeH₄Me-4)(OEt)₂ and P(O)(NMeC₆H₄Me-4)₂(OEt), the chlore- and ethoxy-derivative of a novel eight-membered heterocyclic system, P(O)(NMeC₆H₄MeC₆H₃Me-4)₂ CH₂-2,2′] (X=Cl or OET), as well as two organic products, CH₂(C₆H₃Me-5-NHMe-2)₂ and CH₂ (C₆H₃Me-5-NMe₂-2)(C₆H₃ Me-5-NMe₂-2) were isolated. The reaction of thiophosphoryl chloride, P(S)Cl₃, with N,N-dimethyl-p-toluidine also gave a similar heterocycle, P(S)Cl[(NMeC₆H₃Me-4)₂CH₂-2,2′]. The ¹H NMR spectra are discussed and related to the X-ray crystal structures.