SYNTHESIS OF DIETHYL 3-ARYL-3-OXOPROPYLPHOSPHONATES
作者:Jen-Wen Yu、Steve K. Huang
DOI:10.1080/00304949709355187
日期:1997.4
ELECTRONIC EFFECT OF SUBSTITUENTS AND MECHANISM ON THE FORMATION OF DIETHYL 3-OXO-3-ARYLPROPYL PHOSPHONATES
作者:Jen-Wen Yu、Chien-Keun Chong、Steve K. Huang
DOI:10.1080/10426509708043563
日期:1997.7.1
The reaction of aryl P-chloroethyl ketones with triethyl phosphite to give gamma-ketophosphonates was studied kinetically. This reaction follows a second order overall and involves a carbonyl group-assisted (CGA) initializing step, followed by a stereoselective pathway to gamma-ketophosphonates. A linear Hammett plot reveals that the rho value is 1.51 (r=0.994), and the transition state is accelerated by the para- halogen on the phenyl group. The results confirm the two-stage mechanism and rule out an S-N(2) mechanism being responsible for the formation of diethyl 3-oxo-3-arylpropyl phosphonates 3.
Photochemical generation of acyl and carbamoyl radicals using a nucleophilic organic catalyst: applications and mechanism thereof
作者:Eduardo de Pedro Beato、Daniele Mazzarella、Matteo Balletti、Paolo Melchiorre
DOI:10.1039/d0sc02313b
日期:——
detail a strategy that uses a commercially available nucleophilic organic catalyst to generate acyl and carbamoyl radicals upon activation of the corresponding chlorides and anhydrides via a nucleophilic acyl substitution path. The resulting nucleophilic radicals are then intercepted by a variety of electron-poor olefins in a Giese-type addition process. The chemistry requires low-energy photons (blue