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Optically active ether lactone, optically active polymer thereof, and process for producing the polymer

Assignee: Takasago International Corp
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Filing: 1992-04-10
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Granted: 1993-06-22
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Expires: 2012-04-10
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Abstract

Abstract An optically active 7-substituted-1,4-dioxepan-5-one derivative represented by the general formula (I): ##STR1## wherein R represents an alkyl group having from 1 to 5 carbon atoms; and * means an asymmetric carbon atom, is disclosed. An optically active polymer represented by formula (II): ##STR2## wherein R and * are as defined above; and n is an integer of 25 or more, obtained by ring opening polymerization of the optically active 7-substituted-1,4-dioxepan-5-one derivative represented by formula (I) is also disclosed. A process for producing the optically active polymer represented by formula (II) is further disclosed, comprising subjecting an optically active 7-substituted-1,4-dioxepan-5-one derivative represented by formula (I) to ring opening polymerization in the presence of at least one catalyst selected from the group consisting of (i) an organotin compound, (ii) an organoaluminum compound and water, and (iii) an organozinc compound and water.

Inventors

  • 👤 Akio Yamaguchi
  • 👤 Yoji Hori
  • 👤 Susumu Akutagawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 16:30
CPC Classifications
C; C07; C07D; C07D321/00; C07D321/02; C07D321/04; C07D321/08

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 32 words
An optically active 7-substituted-1,4-dioxepan-5-one derivative represented by the general formula (I): ##STR8## wherein R represents an alkyl group having from 1 to 5 carbon atoms; and * means as asymmetric carbon atom.
Claim 2
Dependent Claim 32 words
An optically active 7-substituted-1,4-dioxepan-5-one derivative represented by the general formula (I): ##STR8## wherein R represents an alkyl group having from 1 to 5 carbon atoms; and * means as asymmetric carbon atom.

References Cited (Backward Citations)

US4190720A Cited
US4470416A Cited
US5120802A Cited
US5028667A Cited
US5028667B1 Cited
US5082925A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-06-21 1996-12-21 1997-06-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-06-21 2000-12-21 2001-06-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-06-21 2004-12-21 2005-06-22 $7700.00 Window Closed / Lapsed

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