76616-25-6Relevant articles and documents
Catalytic double-bond metathesis without the transition metal
Bell, Stephen A.,Meyer, Tara Y.,Geib, Steven J.
, p. 10698 - 10705 (2002)
Iminophosphoranes of the type X3P=NR (X = CI, pyrrolyl; R = alkyl, aryl) catalytically metathesize C=N bonds of carbodiimides via an addition/elimination mechanism that, despite the lack of d orbital participation in P-N bonding, conserves the key features of metal-catalyzed olefin metathesis. Diazaphosphetidine intermediates, produced by the formal [2 + 2] addition of carbodiimides to the P=N bond, have been isolated and characterized. All phosphorus-containing species in the complex catalytic reaction mixtures have been identified and their origins explained. The kinetics of addition of diisopropylcarbodiimide to Cl3P=NPri and subsequent elimination were studied, and rate constants were determined: kadd 1.7 × 10-3 (±0.1 × 10-3) M s-1 and kelim = 4.0 × 10-4 (±0.3 × 10-4) s-1. The rate of these reactions corresponds well with the observed catalytic TOF of 1.44 TO/P/h.
