EP0079134A1
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EP
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Stereospecific synthesis of 5-phenyl-2S-pentanol
Assignee: Pfizer Inc
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Filing: 1982-10-13
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Granted: —
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Expires: 2002-10-13
Abstract
Abstract 5-Phenyl-2S-pentanol is synthesised stereospecifically from a chiral ketone of the formula: by hydrogenation over a noble metal catalyst: the chiral ketone is preparable from S-ethyl lactate. Also included are certain novel intermediates, including those of the formula (II), useful in these processes. The method provides easily purified 5-phenyl-2S-pentanol useful in the synthesis of central nervous system active (CNS) agents such as levonantradol.
Inventors
- 👤 Berkeley Wendell Cue
- 👤 Bernard Shields Moore
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 13:52
CPC Classifications
C; C07; C07C; C07C309/00; C07C29/00; C07C29/09; C07C29/10; C07C33/00; C07C33/18; C07C33/20; C07C43/00; C07C43/02; C07C43/03; C07C43/14; C07C43/17; C07C43/174; C07C43/178; C07C43/1782; C07C45/00; C07C45/61; C07C45/67; C07C45/673; C07C49/00; C07C49/76; C07C49/84; C07B; C07B2200/00; C07B2200/07
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
9 words
(BE, FR, DE, GB, IT, LU, NL, SE, CH/LI)
Claim 2
Dependent Claim
24 words
A process for preparing 5-phenyl-2S-pentanol of the formula which comprises the hydrogenation over a noble metal catalyst of a chiral ketone of the formula
Claim 3
Dependent Claim
36 words
A process according to claim 1, wherein the chiral ketone of the formula (II) is prepared by the hydrolysis and decarboxylation of a chiral ester of the formula wherein R is (C 1 -C 4 )alkyl.
Claim 4
Dependent Claim
57 words
A process according to claim 2, wherein the chiral ester of the formula (III) is prepared by the reaction of an alkali metal salt of a (C 1 -C 4 )alkyl benzoylacetate with a chiral compound of the formula wherein X is I, Br, Cl, -OSO 2 CH 3 or optionally in the presence of iodide ions.
Claim 5
Dependent Claim
45 words
A process according to claim 3, wherein X is I, Br or Cl, and the chiral compound of the formula (IV) is prepared by the reaction of halide ions with a chiral compound of the formula (IV) wherein X is -OSO 2 CH 3 or
Claim 6
Dependent Claim
43 words
A process according to claim 3 or 4, wherein the chiral compound of the formula (IV) wherein X is -OS0 2 CH 3 or is prepared by the reaction of methanesulfonyl chloride or p-toluene sulfonyl chloride with a chiral compound of the formula
Claim 7
Dependent Claim
73 words
A process according to claim 5, wherein the chiral compound of the formula (V) is prepared by the hydride reduction of a chiral ester of the formula wherein R is (C l- C 4 )alkyl; and wherein the chiral ester of the formula (VI) is prepared by the reaction of benzyl methanesulfonate neat with an excess of a chiral 2S lactate ester of the formula wherein R is (C 1 -C 4 )alkyl.
Claim 8
Dependent Claim
48 words
A process for the preparation of a chiral ester of the formula wherein R is (C 1 -C 4 )alkyl, which comprises the reaction of benzyl methanesulfonate neat with an excess of a chiral 2S lactate ester of the formula wherein R is (C 1 -C 4 )alkyl.
Claim 9
Dependent Claim
18 words
A chiral ketone of the formula wherein Y is hydrogen or -COOR where R is (C 1 -C4)alkyl.
Claim 10
Dependent Claim
18 words
A chiral ketone as claimed in claim 8 wherein Y is hydrogen or -COOC 2 H 5 .
Claim 11
Dependent Claim
11 words
A chiral compound of the formula wherein X is I, Br,
References Cited (Backward Citations)
EP0032659A1
Cited
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