74629-17-7Relevant academic research and scientific papers
Mesoionic compounds. Part 10. A Study of the Reactions of 3-(3-Pyridyl)sydnone with Some Nucleophilic Reagents
Greco, Claude V.,Mehta, Jitendra R.
, p. 20 - 26 (2007/10/02)
Nucleophilic addition of organo-magnesium and -lithium reagents to 3-(3-pyridyl)sydnone (1) afforded 4-substituted-3-(sydnon-3-yl)-1,4-dihydropyridines (7), accompanied by lesser amounts of the 1,2-dihydropyridine isomers (8).The mixtures were separated by t.l.c. and the isomers examined by u.v. spectroscopy.The structures of the pure dihydropyridines (7, R = Et, Bun, or PhCH2) were further established by 1H n.m.r. spectroscopy.Sodium borohydride in aprotic or protic solvents reduced (1) to 3-(sydnon-3-yl)-1,4-dihydropyridine (10) or 3-(sydnon-3-yl)-1,4,5,6-tetrahydropyridine (11) respectively. 1-Alkyl-3-(sydnon-3-yl)pyridinium iodides (12a and 12b) with potassium cyanide gave respective 1-alkyl-4-cyano-3-(sydnon-3-yl)-1,4-dihydropyridines (13a) and (13b).Methylmagnesium bromide favoured formation of -magnesium bromide (3a) over dihydropyridine adducts (4a) and (5a) and was employed in the preparation of alcohols (14)-(23) which were dehydrated with trifluoroacetic acid to their respective (3-pyridyl)sydnon-3-yl-substituted alkenes (27)-(31).
