Regioselective Synthesis of Indolyldihydropyridines. A Remarkable Solvent Effect
作者:Rodolfo Lavilla、Teresa Gotsens、Joan Bosch
DOI:10.1055/s-1991-26587
日期:——
The synthesis of 1,2-dihydro-2-(3-indolyl)-1-methylpyridines and 1,4-dihydro-4-(3-indolyl)-1-methylpyridines through the addition of indoles to pyridinium salts in various solvents is described. Selective preparation of 1,2-dihydropyridines is possible performing the reaction in methanol as the solvent, whereas the 1,4-isomers are preferentially formed in dimethyl sulfoxide.
Alstoscholarisines H–J (1–3), new monoterpenoid indole alkaloids with an unprecedented skeleton created via the formation of a C-3/N-1 bond, were isolated from Alstonia scholaris. Their structures were established by extensive spectroscopic analyses and the assessment of single-crystal X-ray diffraction data. The totalsynthesis of alstoscholarisine H was achieved via the regioselective nucleophilic addition
Nucleophilic addition of 2-indolylacyl anion equivalents to N-alkylpyridinium salts
作者:M. Lluisa Bennasar、Ester Zulaica、Joan Bosch
DOI:10.1021/jo00036a015
日期:1992.5
The reactions of the anions derived from dithioacetals 1-3 and a-amino nitriles 4 toward pyridinium salts 5 are studied. Depending on the nucleophile used, 2-(dihydropyridylmethyl)indoles 6 and 7, which can be cyclized to tetracyclic methanoazocinindole systems 10 and 11, respectively, or 2-substituted 3-(dihydropyridyl)indoles 8 and 9 are formed.