142301-79-9

Upstream product

• 100-46-9 benzylamine 
• 142301-76-6 Ethyl 5-pent-2-ynoate 
• 142301-75-5 N-(tert-butoxycarbonyl)-N-benzyl-4-amino-1-butyne 
• 142301-78-8 Ethyl 5-pent-2-ynoate 
• 142301-77-7 Ethyl 5-(benzylamino)pent-2-ynoate 
• 107301-61-1 N-benzyl-4-amino-1-butyne 

Downstream Products

• 112548-81-9 (3-Acetyl-1-benzyl-piperidin-4-yl)-acetic acid ethyl ester 

Relevant academic research and scientific papers

Heterocycles in Asymmetric Synthesis. Part 1. Construction of the Chiral Building Blocks for Enantioselective Alkaloid Synthesis via an Asymmetric Intramolecular Michael Reaction

The asymmetric intramolecular Michael reaction of acyclic compounds ethyl (E)-4-but-2-enoate 9, and ethyl (E)-5-pent-2-enoate 10 was investigated under a variety of conditions, and the pyrrolidine ethyl (4-acetyl-1-benzylpyrrolidin-3-yl)acetate 11 and piperidine ethyl (3-acetyl-1-benzylpiperidin-4-yl)acetate 12, versatile chiral building blocks for alkaloid synthesis, were obtained in moderate to excellent optical yield.Cyclization of the aforementioned but- and pent-2-enoate using (R)-1-phenylethylamine in THF in the presence of molecular sieves 5 Angstroem gave the (+)-pyrrolidine derivative (+)-11 and the (-)-piperidine derivative (-)-12 in 60 and 90percent ee, respectively.When (S)-1-phenylethylamine was used, pyrrolidine (-)-11 and piperidine derivatives (+)-12 were obtained in similar optical yields, respectively.The ee of (-)- and (+)-piperidine derivatives increased up to 98percent upon recrystallization of their hydrobromid salts.