A simple, cheap alternative to 'designer convertible isonitriles' expedited with microwaves

This Letter reports on the novel use of n-butylisonitrile as a cheaper, more atom economical alternative to currently reported 'designer' convertible isonitriles in UDC (Ugi/DeProtect/Cyclize) methodology. Transformations to diketopiperazines and 1,4-benzodiazepine-2,5-diones are facilitated by microwave irradiation and proceed in excellent yield.