21328-43-8

Basic information

• Product Name: 1-Cyclohexene-1-carboxylic acid, 2-(1-pyrrolidinyl)-, ethyl ester
• Synonyms: ethyl 2-pyrrolidinylcyclohex-1-enecarboxylate;1-N-Pyrrolidino-2-carboaethoxycyclohex-1-en;2-pyrrolidin-1-yl-cyclohex-1-enecarboxylic acid ethyl ester
• CAS NO: 21328-43-8
• Molecular Formula: C13H21NO2
• Molecular Weight: 223.315
• Mol File: 21328-43-8.mol
• Article Data: 3

Chemical Properties

• CAS DataBase Reference: 1-Cyclohexene-1-carboxylic acid, 2-(1-pyrrolidinyl)-, ethyl ester(CAS DataBase Reference)
• NIST Chemistry Reference: 1-Cyclohexene-1-carboxylic acid, 2-(1-pyrrolidinyl)-, ethyl ester(21328-43-8)
• EPA Substance Registry System: 1-Cyclohexene-1-carboxylic acid, 2-(1-pyrrolidinyl)-, ethyl ester(21328-43-8)

Safety Data

• Hazardous Substances Data: 21328-43-8(Hazardous Substances Data)

Upstream product

• 1125-99-1 1-(1-Cyclohexen-1-yl)pyrrolidine 
• 123-75-1 pyrrolidine 
• 1655-07-8 ethyl 2-oxocyclohexane carboxylate 

Downstream Products

• 42899-29-6 1-acetyl-1,2,3,4,5,6,7,8-octahydro-quinoline 
• 71866-22-3 1-acetyl-2,3,4,5,6,7-hexahydro-1H-[1]pyrindine 
• 82297-58-3 1-(1-cyclohexenmethyl)pyrrolidine 
• 1192-88-7 1-cyclohexene-1-carboxaldehyde 
• 4845-04-9 1-cyclohexene-1-methanol 
• 82297-59-4 2-Pyrrolidin-1-yl-cyclohexanecarboxylic acid ethyl ester 
• 192817-77-9 ethyl 2-pyrrolidinobenzoate 

Relevant articles and documents

Transfer of Alkoxycarbonyl from Alkyl Imidazolium-2-carboxylates to Benzyl Alcohol, a Cyclohexanone Enamine and Diethylamine

Alkylimidazole-2-carboxylates may be alkylated with methyl triflate to give the corresponding N-methylimidazolium salts.These salts react with benzyl alcohol in the presence of 1,4-diazabicyclooctane, with 1-(pyrrolidin-1-yl)cyclohexene and with diethylamine to give benzyl alkyl carbonates, an enamino ester and a urethane respectively; in one case a tetrahedral intermediate is observed.The corresponding phenyl ester was consumed without attack by benzyl alcohol at the carbonyl group.A 2-cyanoimidazolium salt underwent similar ill-defined consumption whereas a 2-dimethylaminocarbonyl derivative remained unchanged. 2-Methylsulfonylimidazolium salts suffered attack by benzyl alcohol at the ring C-2.

ENAMINE CHEMISTRY-XXV REDUCTION OF ENAMINONONES BY LiAlH4 AND NaBH4 SYNTHESIS OF α,β-UNSATURATED ALDEHYDES

Cyclohexanone, 2-methyl-cyclohexanone and 4-methyl-cyclohexanone, 1, were transformed into the enaminones 4a-4e by the following two routes: (A): Acylation of the enamines, 2, derived from 1 and secondary amines (pyrrolidine, morpholine and piperidine) by ethyl chloroformate, and (B): Condensation of 1 with diethyl oxalate, giving the β-ketoesters 3, followed by reaction with the secondary amines.Ethyl 2(-1-pyrrolidinyl)-1-cyclopentene-1-carboxylate. 4f, and methyl 3-(1-pyrrolidinyl)-2-buteonate, 4g, were prepared from ethyl 2-oxo-1-cyclopentanecarboxylate and ethyl 3-oxo-butanoate, respectively, by condensation with pyrrolidine.Reduction of 4a by LAH afforded 1-cyclohexen-1-carboxaldehyde, 5a, 1-cyclohexene-1-methanol, 6a, and 1-(1-cyclohexene-1-methyl)pyrrolidine, 7a, in yields depending on the molar ratio of LAH/4a.Reduction of 4f by LAH gave cyclopenten-1-methanol, 6b, 1-(1-cyclopentene-1-methyl)pyrrolidine, 7b, and ethyl-2(1-pyrrolidinyl)-1-cyclopentanecarboxylate, 8b.Compound 4g, when reduced with LAH, yielded methyl 3-(1-pyrrolidinyl) butanoate, 8c (main product) and 1-(2-butenyl)pyrrolidine, 7c (minor).Reduction of 4 by NaBH4 afforded exlusively the saturated β-aminoesters, 8, in high yields.The reductions with LAH and NaBH4 are rationalized in terms of the HSAB principle.