Oxidative desulfurization of disubstituted thioureas using Pb(II) salts and investigation of p<i>K</i><sub>a</sub>-dependent regioselective N-acylation
                                
                                    
                                        作者:Harisadhan Ghosh、Soumya Sarkar、Abdur Rezzak Ali、Bhisma K. Patel                                    
                                    
                                        DOI:10.1080/17415990903295686
                                    
                                    
                                        日期:2010.2
                                    
                                    A highly efficient method for the N-acylation of both symmetrical and unsymmetrical thioureas by the use of lead (II) salts and triethylamine has been achieved. The reaction gives regioselective N-acylated product for unsymmetrical thiourea. For unsymmetrical thiuourea, regioselective N-acylation takes place towards the amine having lower pKa. A linear correlation between the pKas of the amines and the regioselective N-acylation is found. Another attractive feature of this transformation is that lead sulfide, which is important to material science, is obtained as a side product (nanocubes of 20nm).