The advice comes from information written by Jenny Dean of the Intermediate Technology Development Group in Britain.

VOA: special.2010.08.02

And what it's used is to convert one type of group, what's called a carboxylic acid into another type of very reactive intermediate, which is called an acid chloride.

它被用来将一类被称作羧酸的化合物，转化成另外一类活性很高的反应中间体,也就是酰氯。

麻省理工公开课 - 化学原理课程节选