One-Step Formation of N-Alkenyl-malonamides and N-Alkenyl-thiomalonamides from Carbamoyl Meldrum's Acids

Thermal Decomposition of Carbamoyl Meldrum's Acids: A Starting Point for the Preparation of 1,3‐Oxazine Derivatives

“…Depending on the type of Meldrum's acid derivative used and in addition the conditions of the process, various compounds can be prepared, for example, β‐lactams , 1,3‐oxazinones , pilicides , isooxazolols , tetramic acid derivatives , cyclic nitrones , prodigiosin family antibiotics analogs, or substituted pyridines . Also, valuable noncyclic compounds can be easily prepared using Meldrum acid as a β‐ketoacylium synthon, for example, we can cite formation of 1,3‐diones , ketoesters , and ketoamides . The main stream of the aforementioned reactions of Meldrum's acid derivatives is connected with their tendency to form ketenes during thermal decomposition; once formed, ketene may react with various types of nucleophiles.…”