An efficient synthesis of 2-(guaiazulen-1-yl)furan derivatives via intramolecular Wittig reactions

An efficient and mild synthesis of 2-(guaiazulen-1-yl)furans, starting from readily available 1-(3-aryl-2-cyanopropenoyl)guaiazulenes, tributylphosphine and acyl chlorides, is described. The strategy employs the intramolecular Wittig protocol as a key step to append the crucial furan ring, leading to the highly functional furans in good yields. An efficient and mild synthesis of 2-(guaiazulen-1-yl)furans, starting from easily accessible 1-(3-aryl-2-cyanopropenoyl)guaiazulenes, tributylphosphine and acyl chlorides, is described. The strategy employs the intramolecular Wittig protocol as a key step to append the crucial furan ring, leading to the highly functional furans in good yields.