Continuous Flow Acylation of (Hetero)aryllithiums with Polyfunctional
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‐Dimethylamides and Tetramethylurea in Toluene
作者:Dimitrije Djukanovic、Benjamin Heinz、Francesca Mandrelli、Serena Mostarda、Paolo Filipponi、Benjamin Martin、Paul Knochel
DOI:10.1002/chem.202102805
日期:2021.10.7
The continuous flow reaction of various aryl or heteroaryl bromides in toluene in the presence of THF (1.0 equiv) with sec-BuLi (1.1 equiv) provided at 25 °C within 40 sec the corresponding aryllithiums which were acylated with various functionalized N,N-dimethylamides including easily enolizable amides at −20 °C within 27 sec, producing highly functionalized ketones in 48–90 % yield (36 examples)
各种芳基或杂芳基溴化物在 THF(1.0 当量)与sec- BuLi(1.1 当量)存在下在甲苯中的连续流动反应,在 25°C 下在 40 秒内提供相应的芳基锂,该芳基锂被各种官能化的N、N -酰化二甲基酰胺,包括易于烯醇化的酰胺,可在 -20 °C 下在 27 秒内以 48-90% 的产率生成高度官能化的酮(36 个实例)。该方法非常适用于制备 α-手性酮,例如萘普生和布洛芬衍生的酮,其ee为 99% 。两种不同的锂有机金属化合物与 1,1,3,3-四甲脲 (TMU) 的一锅逐步双加成以 69-79% 的产率提供不对称酮(9 个例子)。