The mechanochemical technique of ball milling has been applied to the solventless and eco-friendly synthesis of chalcogenides (sulfide and selenide) of a variety of tertiary and aminophosphines. In most of the cases, the products are obtained in almost quantitative yields with high purity by applying a simple workup procedure without using chromatographic techniques or any other purification methods. The scope of this methodology was explored by using a range of phosphines (mono, di and tetra) to synthesize partial as well as mixed chalcogenides. The use of almost equimolar amounts of starting materials and the absence of any byproducts significantly simplifies the product isolation compared with the standard solution state reactions, thus providing a highly atom economic (100%) method with an ideal E-factor (E = 0). The solid-state reactions were monitored by P-31H-1 NMR spectroscopy. The structures of some of the products are also confirmed by single-crystal X-ray analyses. Although most of the reactions were carried out on ca. 100-mg scale, the scaling up of the reaction did not affect the course of the reaction.
Cheruy et al. (Wed,) studied this question.