Processes for preparing a 3-isopropenyl-6-heptenal compound and a 6- isopropenyl-3-methyl-3,9-decadienyl carboxylate compound, and an intermediate therefor

Patent metadata

Field	Value
Publication number	US-11807602-B2
Application number	US-202117543877-A
Country	US
Kind code	B2
Filing date	Dec 7, 2021
Priority date	Dec 10, 2020
Publication date	Nov 7, 2023
Grant date	Nov 7, 2023

Abstract

The present invention relates to a process for preparing a 3-isopropenyl-6-heptenal compound of the following formula (2): wherein R 1 represents a hydrogen atom or a methyl group, the process comprising: subjecting a 3-isopropenyl-6-heptenoate ester compound of the following formula (1): wherein R 1 is as defined above, and R 2 represents a monovalent hydrocarbon group having 1 to 10 carbon atoms, to a reduction reaction with a reducing agent to form the 3-isopropenyl-6-heptenal compound (2).

First claim

The invention claimed is:

1. A process for preparing a 3-isopropenyl-6-heptenal compound of the following formula (2):

wherein R 1 represents a hydrogen atom or a methyl group,
the process comprising:
subjecting a 3-isopropenyl-6-heptenoate ester compound of the following formula (1):

wherein R 1 is as defined above, and R 2 represents a monovalent hydrocarbon group having 1 to 10 carbon atoms,
to a reduction reaction with a reducing agent to form the 3-isopropenyl-6-heptenal compound (2), wherein the reducing agent is selected from a group consisting of a complex hydride, an alkoxy derivative of the complex hydride, and an alkyl derivative of the complex hydride.

2. A process for preparing a 6-isopropenyl-3-methyl-3,9-decadienyl carboxylate compound of the following formula (4):

wherein R 1 represents a hydrogen atom or a methyl group, and R 3 represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms,
the process comprising:
the process for preparing the 3-isopropenyl-6-heptenal compound (2) according to claim 1 ;
subjecting the 3-isopropenyl-6-heptenal compound (2) thus obtained to a four-carbon homologation reaction including a Wittig reaction, using an ethyltriphenylphosphonium halide compound and ethylene oxide to form a 6-isopropenyl-3-methyl-3,9-decadienol compound of the following formula (3):

wherein R 1 is as defined above; and
subjecting the 6-isopropenyl-3-methyl-3,9-decadienol compound (3) thus obtained to an esterification reaction to form the 6-isopropenyl-3-methyl-3,9-decadienyl carboxylate compound (4).

3. The process for preparing the 3-isopropenyl-6-heptenal compound (2) according to claim 1 , the process further comprising:
subjecting a 4-pentenyltriphenylphosphonium halide compound of the following formula (5):

wherein R 1 is as defined above, Ph represents a phenyl group, and X represents a halogen atom,
to a Wittig reaction with a 2-propanone compound of the following formula (6) having a protected hydroxyl group:

wherein R 4 represents a protective group for a hydroxyl group,
to form a 2-methyl-2,6-heptadiene compound of the following formula (7) having a protected hydroxyl group at position 1:

wherein R 1 and R 4 are as defined above;
removing the protective group from the 2-methyl-2,6-heptadiene compound (7) having a protected hydroxyl group at position 1 to form a 2-methyl-2,6-heptadienol compound of the following formula (8):

wherein R 1 is as defined above; and
subjecting the 2-methyl-2,6-heptadienol compound (8) thus obtained to a Johnson-Claisen rearrangement with an orthoacetate ester compound to form the 3-isopropenyl-6-heptenoate ester compound (1).

4. The process for preparing the 3-isopropenyl-6-heptenal compound (2) according to claim 1 , the process further comprising:
subjecting a 4-pentenyltriphenylphosphonium halide compound of the following formula (5):

wherein R 1 represents a hydrogen atom or a methyl group, Ph represents a phenyl group, and X represents a halogen atom,
to a Wittig reaction with a 2-propanone compound of the following formula (6) having a protected hydroxyl group:

wherein R 4 represents a protective group for a hydroxyl group,
followed by removal of the protective group to form a 2-methyl-2,6-heptadienol compound of the following formula (8):

wherein R 1 is as defined above; and
subjecting the 2-methyl-2,6-heptadienol compound (8) thus obtained to a Johnson-Claisen rearrangement with an orthoacetate ester compound to form the 3-isopropenyl-6-heptenoate ester compound (1).

5. The process for preparing the 6-isopropenyl-3-methyl-3,9-decadienyl carboxylate compound (4) according to claim 2 , the process further comprising:
subjecting a 4-pentenyltriphenylphosphonium halide compound of the following formula (5):

wherein R 1 represents a hydrogen atom or a methyl group, Ph represents a phenyl group, and X represents a halogen atom, to a Wittig reaction with a 2-propanone compound of the following formula (6) having a protected hydroxyl group:

wherein R 4 represents a protective group for a hydroxyl group,
to form a 2-methyl-2,6-heptadiene compound of the following formula (7) having a protected hydroxyl group at position 1:

wherein R 1 and R 4 are as defined above;
removing the protective group from the 2-methyl-2,6-heptadiene compound (7) having a protected hydroxyl group at position 1 to form a 2-methyl-2,6-heptadienol compound of the following formula (8):

wherein R 1 is as defined above;
subjecting the 2-methyl-2,6-heptadienol compound (8) thus obtained to a Johnson-Claisen rearrangement with an orthoacetate ester compound to form the 3-isopropenyl-6-heptenoate ester compound (1).

6. The process for preparing a 6-isopropenyl-3-methyl-3,9-decadienyl carboxylate compound (4) according to claim 2 , the process further comprising:
subjecting a 4-pentenyltriphenylphosphonium halide compound of the following formula (5):

wherein R 1 represents a hydrogen atom or a methyl group, Ph represents a phenyl group, and X represents a halogen atom, to a Wittig reaction with a 2-propanone compound of the following formula (6) having a protected hydroxyl group:

wherein R 4 represents a protective group for a hydroxyl group,
followed by removal of the protective group to form a 2-methyl-2,6-heptadienol compound of the following formula (8):

wherein R 1 is as defined above; and
subjecting the 2-methyl-2,6-heptadienol compound (8) thus obtained to a Johnson-Claisen rearrangement with an orthoacetate ester compound to form the 3-isopropenyl-6-heptenoate ester compound (1).

7. A process for preparing a 3-isopropenyl-6-heptenoate ester compound of the following formula (1):

Assignees

• Shinetsu Chemical Co

Inventors

• Baba Akihiro
• Kinsho Takeshi
• Ishibashi Naoki
• Nagae Yusuke

Classifications

• C07C69/587 Primary

  Monocarboxylic acid esters having at least two carbon-to-carbon double bonds · CPC title

• C07C45/41 Primary

  by hydrogenolysis or reduction of carboxylic groups or functional derivatives thereof · CPC title

• C07C67/08

  by reacting carboxylic acids or symmetrical anhydrides with the hydroxy or O-metal group of organic compounds · CPC title

• C07C67/27

  from ortho-esters · CPC title

• C07C67/475

  by splitting of carbon-to-carbon bonds and redistribution, e.g. disproportionation or migration of [IMAGE cpc-sch-C07C-0963.gif] groups between different molecules · CPC title