405512-96-1

Upstream product

• 379679-67-1 3-methoxy-2-(4-fluorophenyl)-2-cyclopenten-1-one 
• 379679-70-6 2-(4-fluorophenyl)-1,3-cyclopentanedione 
• 379679-62-6 3-bromo-2-(4-fluorophenyl)-2-cyclopenten-1-one 
• 5870-62-2 3-hydroxy-2-cyclopenten-1-one 
• 190269-78-4 (1R,2R,3S)-2-(4-fluorophenyl)-3-hydroxycyclopentane-1-carboxylic acid 
• 190269-75-1 methyl (1R,2R,3S)-2-(4-fluorophenyl)-3-hydroxycyclopentane-1-carboxylate 
• 379679-64-8 methyl 2-(4-fluorophenyl)-3-oxo-1-cyclopent-1-enecarboxylate 

Downstream Products

• 405512-97-2 (1S,2R,3R)-3-(tert-butyldimethylsilanyloxymethyl)-2-(4-fluorophenyl)cyclopentanol 
• 912807-36-4 (R)-1-[(1R,2R,3S)-3-{(R)-1-(3,5-bis(trifluoromethyl)phenyl)ethoxy}-2-(4-fluorophenyl)cyclopentylmethyl]piperidine-3-carboxylic acid tert-butyl ester 
• 405512-99-4 [(1R,2R,3S)-3-{1-(3,5-bis(trifluoromethyl)phenyl)vinyloxy}-2-(4-fluorophenyl)cyclopentylmethoxy]tert-butyldimethylsilane 
• 912807-20-6 3,5-bis(trifluoromethyl)benzoic acid (1S,2R,3R)-3-(tert-butyldimethylsilanyloxymethyl)-2-(4-fluorophenyl)cyclopentyl 
• 190266-45-6 [(1R,2R,3S)-3-{(R)-1-(3,5-bis(trifluoromethyl)phenyl)ethoxy}-2-(4-fluorophenyl)cyclopentyl]methanol 

Relevant academic research and scientific papers

Stereoselective preparation of a cyclopentane-based NK1 receptor antagonist bearing an unsymmetrically substituted sec-sec ether

A highly efficient synthesis of the potent and selective NK-1 receptor antagonist 1 is described. The key transformation involved the etherification reaction between cyclopentanol 12 and chiral imidate 30 which was catalyzed by HBF4 to initially give ether 14 as a 17:1 mixture of diastereomers and in 75% combined yield. The diastereoselectivity was upgraded to 109:1 by crystallization of the triethylamine solvate 44 which was isolated in 54% yield from 12. Mechanistic studies confirmed that the etherification reaction proceeds through an unprecedented SN2 reaction pathway under typical S N1 reaction conditions.

Asymmetric synthesis of 1,2,3-trisubstituted cyclopentanes and cyclohexanes as key components of substance P antagonists

An efficient asymmetric synthesis of 1,2,3-trisubstituted cyclopentanes and cyclohexanes is described. Three methods were developed for the preparation of the 2,3-disubstituted cyclopentenones and cyclohexenones, which are key achiral building blocks. These intermediates are reduced catalytically with (R)-2-methyloxazaborolidine in high yield (82-98%) and excellent ee (89-96%). Directed reduction of the chiral allylic alcohols using Red-Al gives exclusively the 1,2-anti stereochemistry (>99:1). Epimerization of the ester center followed by saponification/crystallization affords the desired hydroxyacids in good yield (65-70%) and in high enantiomeric excess (>99%).