The reaction of trihalogenomethyl anions with carbonyl compounds: competitive reactivity comparisons and applications to the synthesis of α-trihalogenomethyl alcohols
作者:Paul J. Atkins、Victor Gold、Wasfy N. Wassef
DOI:10.1039/p29840001247
日期:——
of trihalogenomethyl anions towards a series of aldehydes relative to their reactivity towards trinitrobenzene. For 4-substituted benzaldehydes, the reactivities obey a linear ρσ– relationship. The most reactive aldehyde used is only two times less reactive towards CCl3– or CBr3– than hydrogen ions, and it is concluded that, in dimethyl sulphoxide solutions, the reaction between trichloromethyl anions
三卤代乙酸和三溴代乙酸在二甲基亚砜溶液中脱羧生成的三卤代甲基阴离子与添加的醛反应。在1,3,5-三硝基苯存在下,与醛的反应与有色迈森海默加合物的形成竞争。从不存在醛的情况下吸光度值的降低,已被用于测量三卤代甲基阴离子对一系列醛的反应性(相对于其对三硝基苯的反应性)。对于4-取代的苯甲醛,其反应性服从线性ρσ–关系。使用的最具反应性的醛与CCl 3 –或CBr 3 –的反应性仅低两倍结论是,在二甲基亚砜溶液中,三氯甲基阴离子与氢离子之间的反应不受控制。与醛的反应已经用于制备式RCH(OY)CX 3的几种新化合物,其中R =芳基或吡啶基,X = Br或Cl,且Y = H或COCH 3。