129784-74-3

Upstream product

• 75-16-1 methylmagnesium bromide 
• 129708-97-0 (5R,9R)-(+)-5-cyanoindolizidine 
• 129708-94-7 (2S)-(-)-2-(4,4-dimethoxybutyl)-1-((1S)-1-phenylethyl)-pyrrolidine 
• 276240-12-1 (2S,2R,6S)-(+)-2-[2-(2-[1,3]-dioxolan-2-yl-ethyl)-6-methyl-3,6-dihydro-2H-pyridin-1-yl]-2-phenylethanol 
• 129708-96-9 (2S)-(-)-2-(4,4-dimethoxybutyl)pyrrolidine 
• 126017-85-4 N-<(S)-1'-Phenylethyl>-5-prop-2''-enylpyrrolidin-2-one 
• 276239-73-7 (3R,5S,8aR)-5-methyl-3-phenyl-2,3,8,8a-tetrahydro-2H-oxazolo[3,2-a]pyridine 

Relevant academic research and scientific papers

Stereocontrolled alkylation of chiral pyridinium salt toward a short enantioselective access to 2-alkyl- and 2,6-dialkyl-1,2,5,6- tetrahydropyridines

Treatment of salts 1a-b with Grignard reagents gives, after reduction of the resulting unstable dihydropyridines 7, the tetrahydropyridines 8a-c, with modest selectivities but in very few steps and under practical conditions. Higher stereo and regioselectivities are obtained with salt 1c which gives the tetrahydropyridines 15a-e. In addition, the dihydropyridine intermediates 11b cyclize to give the new oxazolidine derivatives 12a-e, which turn out to be good precursors of the 2,6-trans-disubstituted tetrahydropyridines 21a-e. Selective syntheses of (-)-lupetidin, (+)-solenopsin, and indolizidines (-)-5 and (-)-6 are presented as representative examples of applications.

Enantioselective Total Syntheses of Indolizidine Alkaloids 167B and 209D

Enantioselective total syntheses of the indolizidine alkaloids 167B and 209D are described.The sytheses proceed via a common late-stage intermediate, amino nitrile 8.Each alkaloid was prepared in 10 steps and approximately 23percent overall yield from (S)