Convenient and practical one-pot synthesis of 4-chloropyrimidines via a novel chloroimidate annulation

Article abstract of DOI:10.1021/op1002352

Reaction of aromatic or heteroaromatic 2-acyl(amino)nitriles with phosphorus pentachloride triggers a novel chloroimidate cyclization, leading directly to the corresponding annullated 4-chloropyrimidines in good to excellent yields. The reaction lends itself to the telescoped one-pot construction of 4-functionalized pyrimidines from the corresponding (hetero)aromatic 2-aminonitriles. For a pyrazolopyrimidine development intermediate, this reaction was scaled up to multikilogram scale with excellent results. A total of 10 examples with different substrates are provided. This one-pot reaction provides an attractive and sustainable alternative to the commonly used multistep methodology for this transformation.