Efficient Medium Ring Size Bromolactonization Using a Sulfur-Based Zwitterionic Organocatalyst
                                
                                    
                                        作者:Yi An Cheng、Tao Chen、Chong Kiat Tan、Jun Jie Heng、Ying-Yeung Yeung                                    
                                    
                                        DOI:10.1021/ja307210n
                                    
                                    
                                        日期:2012.10.10
                                    
                                    Catalytic bromolactonization of long-chain olefinic acids resulting in the efficient synthesis of medium-sized lactones is reported using a zwitterionic catalyst and stoichiometric N-bromosuccinimide halogen source. The reaction was found to be more efficient at 0 degrees C than at room temperature, which could be attributed to the temperature dependence of the zwitterionic catalyst.