Kinetics and Mechanism of the Pyridinolysis of Phenacyl Bromides in Acetonitrile
作者:Han Joong Koh、Kwang Lae Han、Hai Whang Lee、Ikchoon Lee
DOI:10.1021/jo000411y
日期:2000.7.1
studies of the reactions of substituted phenacyl bromides (YC6H4COCH2Br) with pyridines (XC5H4N) are carried out in acetonitrile at 45.0 degrees C. A biphasic Bronsted plot is obtained with a change in slope from a large (betaX approximately equals 0.65-0.80) to a small (betaX approximately 0.36-0.40) value at pKa = 3.2-3.6, which can be attributed to a change in the rate-determiningstep from breakdown
Efficient synthesis of indolizines and new imidazo[1,2-a]pyridines via the expected cyclization of aromatic cycloimmonium ylides with electron deficient alkynes and ethyl cyanoformate
作者:C. Sandeep、Basavaraj Padmashali、Rashmi S. Kulkarni
DOI:10.1016/j.tetlet.2013.09.033
日期:2013.11
Aromatic cycloimmonium ylides underwent smooth cyclization with electron deficient alkynes in presence of anhydrous K2CO3 in DMF solvent at room temperature to afford substituted indolizines. Ylides have also undergone expected cyclization with ethyl cyanoformate to produce imidazo[1,2-a]pyridines. The structures of these newly synthesized compounds have been confirmed by spectroscopic techniques and
在室温下,在DMF溶剂中,在无水K 2 CO 3的存在下,用缺电子炔烃对芳族环亚胺基进行平滑环化反应,得到取代的吲哚嗪。氰化物也已用氰基甲酸乙酯进行了预期的环化反应,生成了咪唑并[1,2- a ]吡啶。这些新合成的化合物的结构已通过光谱技术和X射线衍射研究得到证实。
Cu(OAc)<sub>2</sub>–Et<sub>3</sub>N mediated oxidative coupling of α-azido ketones with pyridinium ylides: utilizing in situ generated imines for regioselective synthesis of imidazo[1,2-a]pyridines