NICOTINIC ACID CROWN ETHERS: SYNTHESIS, COMPLEXATION AND REDUCTION

Article abstract of DOI:10.1016/S0040-4020(01)91918-0

2,6-Bis(bromomethyl)nicotinic oxazoline (15), prepared from ethyl 2,6-dimethylnicotinate, was converted into the 1:1-macrocyclic oxazolines 19 and 22 as well as the isomeric macrocyclic dimers 20.Ethyl 2,6-bis(bromomethyl)nicotinate (23), prepared from 6b, was converted to the corresponding 1:1-dibenzo-18-crown-6 macrocyclic analog 24.NMR and mass spectral data were used to ascertain the macrocyclic structures.Reaction of 22 with EtMgBr afforded, after oxidation, the 4-substituted pyridino macrocycle 26 in high yield.However, under identical conditions, the non-oxazoline macrocycle 27 was recovered in toto.