Halogen–lithium exchange versus deprotonation: regioselective mono- and dilithiation of aryl benzyl sulfides. A simple approach to α,2-dilithiotoluene equivalents
作者:Tomasz Kliś、Janusz Serwatowski、Grzegorz Wesela-Bauman、Magdalena Zadrożna
DOI:10.1016/j.tetlet.2010.01.074
日期:2010.3
reactions between aryl benzyl sulfides and alkyllithiums were investigated. The resultant mono- and dilithiated intermediates were converted into the corresponding aldehydes and boronic, or carboxylic acids in good yields. It was found that diethyl ether stabilizes the ortho-lithiated compounds toward isomerisation to the benzylic derivatives. The process occurs easily in THF at low temperature and is
研究了芳基苄基硫醚和烷基锂之间的卤素-锂交换和去质子反应。将得到的单和双锂化的中间体以良好的产率转化为相应的醛和硼或羧酸。发现二乙醚使邻位锂化的化合物稳定化,使其异构化为苄基衍生物。该过程很容易在低温下的THF中发生,并且是容易获得α,2-二硫代甲苯衍生物的途径,该衍生物在用CO 2处理后可以转化为二羧酸。