2432-84-0

Usage

Synthesis Reference(s)

Synthesis, p. 302, 1981 DOI: 10.1055/s-1981-29427

Upstream product

• 111-64-8 n-octanoic acid chloride 
• 75-08-1 ethanethiol 
• 5573-62-6 (ethylthio)trimethylsilane 
• 124-13-0 Octanal 
• 90467-73-5 2-(n-heptyl)-1,3-oxathiolane 
• 124-07-2 Octanoic acid 

Downstream Products

• 148615-28-5 (R)-1-phenylethyl octanoate 
• 148531-92-4 (R)-1-cyclohexylethyl octanoate 
• 148615-29-6 (1R,2R)-trans-2-methylcyclohexyl octanoate 
• 181962-57-2 Octanoic acid (1R,2S)-2-methyl-cyclohexyl ester 
• 1248350-23-3 C₁₈H₂₆O₂ 
• 185427-33-2 trans-1,2-Bis-octanoyloxy-cyclohexan 
• 117707-38-7 (R)-2-octyl octanoate 
• 75-08-1 ethanethiol 

Relevant academic research and scientific papers

Kinetic resolution of chiral auxiliaries with C2-symmetry by lipase-catalyzed alcoholysis and aminolysis

Three cyclic diols, 1,2-cyclohexanediol (1), 1,3-cyclohexanediol (2), and 1,3-cyclopentanediol (3), two acyclic unsaturated diols, 1,5-hexadiene-3,4-diol (4) and 1,7-octadiyne-3,6-diol (5), and a cyclic diamine, 1,2-cyclohexanediamine (6), have been kinetically resolved in alcoholysis and aminolysis reactions, catalyzed by Candida antarctica component B lipase, using S-ethyl thiooctanoate or ethyl octanoate as acyl donors. Acceptable stereoselectivity was achieved in most cases. Acta Chemica Scandinavica 1996.

Candida antarctica Lipase B Catalysed Kinetic Resolutions: Substrate Structure Requirements for the Preparation of Enantiomerically Enriched Secondary Alcanols

The lipase B of the Candida antarctica yeast displays high enantioselectivity in transesterification reactions with chiral secondary alcohols in non-aqueous media.This was exploited to resolve a series of racemates structurally related to 2-octanol, namely 3-hydroxy-1-undecyne, 3-hydroxy-1-nonene, 3-nonanol, 1-chloro-2-octanol, 2-methyl-3-nonanol, 2,2-dimethyl-3-nonanol.The substrates were designed to probe the alcohol binding part of the active site of the lipase.The first four racemates could be resolved to produce compounds of high enantiomeric purity.A lipase catalysed transesterification of 1-chloro-2-octanol was observed. 2-Methyl-3-nonanol and 2,2-dimethyl-3-nonanol did not form any detectable amounts of product ester.The kinetic resolutions of the alcohols were performed with S-ethyl thiooctanoate as the acyl donor.

Preparation of 1-Pyridinylethanols of High Enantiomeric Purity by Lipase Catalysed Transesterifications

Component B lipase of the Candida antarctica yeast displays high enantioselectivity in catalysing transesterification reactions in non-aqueous media with chiral secondary alcohols.This was exploited to resolve racemates of 1-(pyridinyl)-ethanols, 1-(6-bromopyridin-2-yl)ethanol, and 1-(6-bromopyridin-2-yl)-2,2-dimethylpropanol.The lipase esterified the (R)-alcohols of the first four substrates in equal or more than 99percent enantiomeric excess in less than three hours with 30-40percent isolated yield.Remaining (S)-enantiomers were isolated in similar yields and in 97-98percent ee. 1-(6-Bromopyridin-2-yl)-2,2-dimethylpropanol did not form any detectable ester in one week.

Resolution of Diols with C2-Symmetry by Lipase Catalysed Transesterification

S-Ethyl thiooctanoate was used as acyl donor in the transesterification of 2,3-butanediol (1), 2,4-pentanediol (2), and 2,5-hexanediol (3), catalysed by a lipase from Candida antarctica.Mixtures of all stereoisomers were used as substrates in each case. 2,5-Hexanediol was transesterified with high stereoselectivity and the (2S,5S)-2,5-hexanediol was isolated in good yield with >99percent ee.The diester of (2R,5R)-2,5-hexanediol was formed in good yield and was hydrolysed to yield the (2R,5R)-2,5-hexanediol of high enantiomeric excess (>99percent ee).Similar results were obtainedfor 2,4-pentanediol with >99percent ee for both enantiomers.The stereoselectivity for 2,3-butanediol was lower than for 2 and 3, giving 89percent ee for the R,R-enantiomer and 34percent ee for the S,S-enantiomer.

S-ethyl thiooctanoate as acyl donor in lipase catalysed resolution of secondary alcohols

The use of S-ethyl thiooctanoate as acyl donor in resolution of secondary alcohols by lipase catalysed transesterification, resulted in an efficient displacement of the equilibrium towards esterification of the alcohol. A lipase (component B) from Candida antarctica was used as the catalyst. On a semi-preparative scale, 0.5 g of 2-octanol was resolved in less than one hour, affording an enantiomeric excess of >98% of the remaining alcohol and >97% of the produced ester. Three other alcohols, 1-phenyl ethanol, 1-cyclohexyl ethanol and trans-2-methyl cyclohexanol were also resolved with good optical yields. After 50% conversion on a preparative scale, 15 g of alcohol, the (S)-enantiomer of 2-octanol could be obtained with an enantiomeric excess of 96%. The (R)-enantiomer was isolated with an enantiomeric excess of 97% after hydrolysis of the produced ester.

ACTIVITY OF 1-OXA-3-THIACYCLOALKANES AND 2-ALKYLTHIOOXACYCLANES IN FREE-RADICAL ISOMERIZATION

It was established that radical isomerization to alkyl esters of thiocarboxylic acids, initiated by tert-butyl peroxide at 130-150 deg C, is a common reaction for five-, six- and seven-membered 1-oxa-3-thiacycloalkanes and 2-alkylthiooxacycloalkanes.Under analogous conditions 2-diethylaminotetrahydropyran isomerizes to N,N-diethylvaleramide.The relation between the structure and the reactivity of 1-oxa-3-thiacycloalkanes and 2-alkylthiooxacycloalkanes in free-radical isomerisation was studied by the method of competing reactions.Depending on the ring size, the activity of the 1-oxa-3-thiacycloalkanes increases in the order : 1,3-oxathianes 1,3-oxathiolanes 1,3-oxathiepanes.

SYNTHETIC APPLICATION OF THIOSILANES TO THIOESTERS

Thiosilanes such as ethylthiotrimethylsilane, hexamethyldisilthiane, and t-butylthiotrimethylsilane, react readily with acyl chlorides at room temperature in the presence of potassium fluoride to give the corresponding thioesters in excellent yields.