18629-11-3Relevant articles and documents
Improved Synthetic Route to Heteroleptic Alkylphosphine Oxides
Kendall, Alexander J.,Seidenkranz, Daniel T.,Tyler, David R.
, p. 2412 - 2417 (2017)
A new method for the synthesis of heteroleptic alkylphosphine oxides (R2R1P=O, where R ≥ R1) from secondary phosphine oxides (or SPOs, R2HP=O) is presented. These reactions were fast at room temperature, sterically selective, high yielding, and >95% pure after an aqueous wash. Deprotonation of an SPO generates a phosphinite anion ([R2P-O]-) that was found to be highly selective for nucleophilic P-C bond formation (as opposed to O-C bond formation) with alkyl halides. Surprisingly, most strong organometallic bases failed to deprotonate SPOs to their respective phosphinite anions (pKas for most SPOs are a very specific base to deprotonate suggests that both ion pairing and the conjugate acid play a role in stabilizing the phosphinite anion. Phosphinite anion reactivity followed the expected trend for an SN2 mechanism on reaction with alkyl halides; elimination products were never observed. A wide variety of heteroleptic alkylphosphine oxides were isolated in near-quantitative yield with only an aqueous wash as purification. This methodology was then used to make new bis(phosphine oxide)alkanes and unsymmetrical α,ω-bis(phosphine oxide)alkanes (R2P(O)(CH2)3P(O)R12) on the benchtop with unprecedented ease.
Sila-Perfumes and Isosteric Perfumes, VII: Reactions and Derivatives of Benzyldialkylphosphinimides
Muenstedt, Rainer,Wannagat, Ulrich
, p. 7 - 18 (2007/10/02)
Derivatives of benzyldialkylphosphinimides C6H5CH2-PRR'=NH(C) with =NCH3, =NSiMe3, =O, =S, -CS2(-) and -NH2>NCS(-) instead of =NH groups (compare Scheme 1) were prepared and characterized.They neither show the H/D exchange of CH2 benzyl protons with CDCl3
