J. Kiji et al., A convenient and general synthetic method for photochromic fulgides by palladium-catalyzed carbonylation of 2-butyne-1,4-diols, MOLEC CRYST, 344, 2000, pp. 235-240
Palladium-catalyzed carbonylation of substituted 2-butyne-1,4-diols affords
a variety of photochromic fulgides in one step. This methodology provides
an alternative to the traditional method based on the Stobbe condensation.