Anomalous products in the acylation of the dicobaltohexacarbonyl complex of 4-methylpenten-3-yne-1 with acryloyl tetrafluoroborate

Acylation of the dicobaltohexacarbonyl complex of 4-methylpenten-3-yne-1 with acryloyl tetrafluoroborate in a medium containing nitromethane with subsequent addition of a nucleophile (methanol or water) leads to anomalous products that are made up of two molecules of starting enyne and one fragment of acryloyl cation. On methanolysis a product of linear structure is formed — a functionally substituted undecane, and on hydrolysis a cyclic product is formed — a functionally substituted dihydropyran.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1875–1879, August, 1989.