89556-97-8

Upstream product

• 89556-96-7 1-Aza-4-(1,3-dithian-2-yl)bicyclo<3.3.0>octan-8-one 
• 97998-13-5 (+/-)-(5β)-6α-vinyl-1-azabicyclo<3.3.0>octan-2-one 
• 97998-04-4 5-Hydroxy-1-((Z)-5-trimethylsilanyl-pent-3-enyl)-pyrrolidin-2-one 
• 97997-92-7 1-((Z)-5-Trimethylsilanyl-pent-3-enyl)-pyrrolidine-2,5-dione 
• 83177-75-7 N-(3-(1,3-Dithian-2-ylidene)propyl)-2,5-pyrrolidinedione 
• 89556-95-6 (7R,7aS)-7-(2-Ethylsulfanyl-[1,3]dithian-2-yl)-hexahydro-pyrrolizin-3-one 
• 83177-77-9 1-Aza-4-<2-(1,3-dithianylidene)>bicyclo<3.3.0>octan-8-one 
• 83177-76-8 1-(3-[1,3]Dithian-2-ylidene-propyl)-5-hydroxy-pyrrolidin-2-one 
• 97998-00-0 1-((E)-5-Trimethylsilanyl-pent-3-enyl)-pyrrolidine-2,5-dione 
• 97998-07-7 5-Hydroxy-1-((E)-5-trimethylsilanyl-pent-3-enyl)-pyrrolidin-2-one 

Relevant academic research and scientific papers

Silicon Directed N-Acyliminium Ion Cyclizations. Highly Selective Syntheses of (+/-)-Isoretronecanol and (+/-)-Epilupinine

Intramolecular reactions of N-acyliminium ions with allyl- and propargylsilanes are described.The cyclization precursors are hydroxy lactams 4b-10b, derived from succinimide and glutarimide, with the ?-nucleophile connected to the nitrogen via an ethylene or propylene chain.Cyclizations are induced by treatment with trifluoroacetic or formic acid and lead to products containing the pyrrolizidine (4c, 7c), indolizidine (5c, 8c), or quinolizidine (6c, 9c) ring system with a vinylidene substituent (propargylsilane cyclization) or a vinyl substituent (allylsilane cyclization).Reactions proceed in high yield with complete regiocontrol (govered by the β-effect of silicon) and with complete stereocontrol (chair-like transition-state conformations).Two allylsilane cyclization products 7c and 9c are further transformed into racemic isoretronecanol (7e) and epilupinine (9e), respectively.

Cationic Cyclizations of Ketene Dithioacetals: A General Synthesis of Pyrrolizidine, Indolizidine, and Quinolizidine Alkaloid Ring Systems

Cyclizations of ketene dithioacetals have been applied to the synthesis of pyrrolizidine, indolizidine, and quinolizidine alkaloid ring systems.This new cationic cyclization terminator allows the efficient formation of 5-, 6-, and 7-membered heterocyclic rings, as illustrated by the preparation of 10a-e.Several of these products, available in three steps, have been converted into the known alkaloids (+/-)-supinidine, (+/-)--trachelanthamidine, (+/-)-elaeokanine A, and (+/-)-epi-lupinine.