Photoredox

A valuable addition to photochemistry, the Merck photoreactor was invented through a collaboration between the MacMillan group and Merck & Co., Inc. This unique design standardizes reaction parameters such as time, light intensity, stir rate, and temperature, all of which can be input via the interactive touch screen on the front panel. Reaction vials are placed inside the cylindrical vessel on top and held above blue LED lights while being surrounded by a reflective lining. The design has been shown to accelerate dramatically reaction times across the board. The information for purchase of this new instrument is provided below.

We use double-density sapphire blue LEDs from Creative Lighting Solutions. They come in two formats: 5-meter spools or precut strips sold by the foot. The precut strips come prefabricated with power connectors. The spools must be cut, soldered to power connectors and then protected with heat-shrink tubing. Both the precut strips or spools require power supplies and cords. The LED strips come with an adhesive back, so they may be easily adhered to the inside of a crystallization dish. We usually use enough length to wrap around a 125 × 65 mm crystallization dish 3–4 times. Reactions are generally placed ~1 cm away from the lights (the walls of the dish), by placing them in a grid from a test tube rack.