New Syntheses of Some Functionalized and Acetylenic β-Keto Phosphonates

Article abstract of DOI:10.1021/jo00097a058

β-Keto phosphonates ω-functionalized by an ester group 1a-f, by a hydroxyl 5, and with a triple bond conjugated to the carbonyl group 2a-c were prepared by reacting dimethyl (lithiomethyl)phosphonate (3) with adequate electrophiles.Cyclic anhydrides such as succinic and glutaric anhydrides were employed for the synthesis of the two first homologs 1a and 1b.To obtain the other longer homologs 1c-f, 3-acylthiazolidine-2-thiones 7a-d easily prepared using cheap 2-mercaptothiazoline proved to be the electrophiles of choice.On the other hand, the synthesis of keto phosphonates 2a-c required the use of N-methoxy-N-methylamides.