Invited Speaker
Prof. Jiaxi Xu
Department of Organic Chemistry, College of ChemistryBeijing University of Chemical Technology, China
Speech Title: Preparation of Poly(benzylphosphinates) as Flame Retardants via in Situ Generated Carbene Insertion
Abstract: Phosphoryl diazoalkanes are a class of important and useful reagents. They have been widely applied as synthetic building blocks in organic and medicinal synthesis. Aryl(diazo)methyl(diaryl)phosphine oxides are one class of phosphory diazomethanes. They reacted with aldehydes and ketones to generate benzo-δ-phosphinolactones, with α,β-enones to give rise to δ-phosphinolactones. When they reacted with cyclic imine dibenzo[b,e][1,4]oxazepines and dibenzo[b,e][1,4]thiazepines to yield corresponding polycyclic benzo-δ-phosphinolactams, while they produced β-phosphinolactams when they reacted with linear imines, especially α,β-enimines. When they reacted with 3-iminoindolinones, spiro β-phosphinolactams were obtained. However, when we prepared ethyl benzyl(diazomethyl)phosphinates from ethyl benzylphosphinochloridates and diazomethane, instead of ethyl benzyl(diazomethyl)phosphinates, ethyl poly(benzylphosphinates) were obtained and exhibited property of flame retardants.
Keywords: Carbene insertion, phosphinate, flame retardant, diazomethane, preparation
References:
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Biography: Prof. Jiaxi Xu is full professor in organic chemistry at College of Chemistry, Beijing University of Chemical Technology. His research interests focus on organic synthetic methodology and related reaction mechanism, especially heterocyclic synthesis and asymmetric catalysis, stereochemistry of β-lactams, β-sultams, and β-phostams and β-phostims, phosphene chemistry, unnatural amino acids and peptides, including α-aminoalkylphosphonic acids, phosphonopeptides, phosphonodepsipeptides, phosphinopeptides, and phosphinodepsipeptides; β-aminoalkanesulfonic acids, sulfonopeptides and hybrid sulfonophosphonopeptides and sulfonophosphinopeptides. https://www.researchgate.net/profile/Jiaxi-Xu-5