Synthesis and NMR Characterization of Heteroarene Substituted N-Silylphosphoranimines

Abstract

Several of the title compounds were prepared by application of the Peterson olefination reaction to the C-silylated phosphoranimine, Me₃SiN=P(OCH₂CF₃)(Me)CH₂SiMe₃ (1). Deprotonation of 1 by treatment with n-BuLi, followed by addition of acetylarenes of arenecarboxaldehydes, and quenching with Me₃SiCl, afforded the phosphoranimine derivatives, Me₃SiN=P(OCH₂CF₃)(Me)CH=C(Ar)R [3a: Ar = 2-C₄H₃O, R=Me; 3b: Ar = 2-C₄H₃S, R = H; 3c: Ar = 2-C₄H₃S, R = Me; 3d: Ar = 2-C₅H₄N, R = H; 3e: Ar = 2-C₅H₄N, R = Me]. These new phosphoranimines (3a-3e) generally formed as mixtures of cis and trans isomers, were obtained as distillable liquids in yields of 60-75% and were fully characterized by NMR (¹H, ¹³C, and ³¹P) spectroscopy and elemental analyses.

Key Words:

• Phosphazene
• phosphoranimine
• heteroarene
• arene
• N-silylphosphoranimine
• N-silyl-P-trifluoroethoxyphosphoranimine