A simple homemade reaction station for use in parallel solution-phase synthesis. optimization of a regioselective one-step deprotective o-formylation reaction mediated by the Vilsmeier-Haack reagent POCl3 center dot DMF

摘要

We report herein the fabrication of a simple and price-affordable portable reaction station for use in parallel solution-phase synthesis. This homemade device uses currently available laboratory components and equipment. Specifically designed to fit standard magnetic hotplates/stirrers, it can simultaneously hold up to 24 heated and magnetically stirred glass reactors of both 10 and 50 mL capacities. Glass reactors are connected by flexible 16-gauge metal needles to a central gas manifold equipped with an inlet/outlet for vacuum and inert gases. Reaction temperatures can be optimally varied from -78 degrees C to 150 degrees C. Using a statistical screening DOE method, this parallel array reactor station has been successfully operated to optimize the one-step deprotective O-formylation of a sterically hindered bis-O-tert-butyldiphenyisilyl (O-TBDPS) aromatic diol. The latter transformation was mediated by the Vilsmeier-Haack reagent POCl3-DMF using a range of Lewis acid and metal salt promoters, including their binary combinations.