Method for production of aldehydes

Details Method for production of aldehydes Method for production of aldehydes

1999-09-13

2001-03-13

Padmanabhan, Sreeni (Department: 1621)

Organic compounds -- part of the class 532-570 series

Organic compounds

Oxygen containing

C568S426000, C568S449000, C568S483000, C568S485000

Reexamination Certificate

active

06201156

ABSTRACT:

TECHNICAL FIELD OF THE INVENTION
The present invention relates to a process for the production of aldehydes. More particularly, it relates to a process for the production of corresponding aldehydes from ethers.
BACKGROUND ART
Aldehyde compounds are important compounds as, for example, pharmaceuticals, agricultural chemicals, perfumes, dyes, and organic intermediates.
As processes for obtaining aldehydes from ethers are known processes using, for example, a peroxide, lead tetraacetate, or copper nitrate as an oxidizing agent. These processes, however, require the use of dangerous reagents and/or metallic compounds in large amounts, and are therefore disadvantageous in handling property and cost efficiency.
Tetrahedron Lett., 1997, 7075 reports that when adamantane is reacted with nitrogen monoxide using N-hydroxyphthalimide as a catalyst, as in the present invention, Ritter reaction proceeds to give corresponding amides. This report lacks, however, a description of a reaction between ethers and nitrogen monoxide.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a process for the production of corresponding aldehydes from ethers in high yields with ease.
After intensive investigations to achieve the above object, the present inventors found that a reaction of ethers with nitrogen monoxide in the presence of a specific catalyst gives corresponding aldehydes in high yields. The present invention has been accomplished based on the above finding.
To be more specific, the invention provides, in an aspect, a process for the production of aldehydes, the process including the step of: reacting an ether represented by the following formula (2):
(wherein R
a
is a hydrogen atom, a hydrocarbon group or a heterocyclic group, R
b
is a hydrogen atom, a hydroxyl group or a substituted oxy group, and R
c
is a hydrocarbon group or a heterocyclic group; R
a
and R
c
may be combined to form a ring with the adjacent carbon atom and oxygen atom)
with nitrogen monoxide in the presence of a catalyst being composed of an imide compound represented by the following formula (1):
(wherein each of R
1
and R
2
is, identical to or different from each other, a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a cycloalkyl group, a hydroxyl group, an alkoxy group, a carboxyl group, an alkoxycarbonyl group, or an acyl group; R
1
and R
2
may be combined to form a double bond, or an aromatic or nonaromatic ring; X is an oxygen atom or a hydroxyl group; and one or two N-substituted cyclic imido groups indicated in the formula (1) may further be formed on the aforementioned R
1
, R
2
, or on the double bond or aromatic or nonaromatic ring formed together by R
1
and R
2
)
to give an aldehyde represented by the following formula (3):
R
a
—CHO  (3)
(wherein R
a
has the same meaning as defined above)
The invention provides, in another aspect, a process for the production of aldehydes, the process including the step of:
reacting an ether represented by the following formula (2a)
(wherein each of R
a1
and R
a2
is, identical to or different from each other, ahydrogenatom, ahydrocarbon group or aheterocyclic group; and each of R
b1
and R
b2
is, identical to or different from each other, a hydrogen atom, a hydroxyl group or a substituted oxy group; R
a1
and R
a2
may be combined to form a ring with the adjacent carbon atom and oxygen atom)
with nitrogen monoxide in the presence of a catalyst being composed of the imide compound represented by the formula (1) to give an aldehyde represented by the following formula (3a-1) and/or (3a-2):
R
a1
—CHO  (3a-1)
R
a2
—CHO  (3a-2)
(wherein each of R
a1
and R
a2
is, identical to or different from each other, a hydrogen atom, a hydrocarbon group or a heterocyclic group; R
a1
and R
a2
may be combined with each other).
In the inventive processes, the amount of the nitrogen monoxide may for example be equal to or more than 5 moles relative to 1 mole of the ether, a substrate.
DETAILED DESCRIPTION OF THE INVENTION
According to the invention, the imide compound represented by the formula (1) is used as a catalyst. Of the substituents R
1
and R
2
in the formula (1), the halogen atom includes iodine, bromine, chlorine and fluorine. The alkyl group includes, for instance, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, s-butyl, t-butyl, pentyl, hexyl, heptyl, octyl, and decyl groups, and other straight- or branched-chain alkyl groups each having about 1 to 10 carbon atoms. As preferred alkyl groups, there may be mentioned, for instance, alkyl groups each having about 1 to 6 carbon atoms, and more preferably lower alkyl groups each having about 1 to 4 carbon atoms.
The aryl group includes phenyl, and naphthyl groups, for example; and the cycloalkyl group includes cyclopentyl, and cyclohexyl groups. As the alkoxy group, there may be mentioned, for example, methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, t-butoxy, pentyloxy and hexyloxy groups, and other alkoxy groups each having about 1 to 10 carbon atoms, preferably about 1 to 6 carbon atoms, of which lower alkoxy groups each having about 1 to 4 carbon atoms are especially preferred.
Examples of the alkoxycarbonyl group include methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, isobutoxycarbonyl, t-butoxycarbonyl, pentyloxycarbonyl and hexyloxycarbonyl groups, and other alkoxycarbonyl groups each having about 1 to 10 carbon atoms in the alkoxy moiety. Preferred alkoxycarbonyl groups include alkoxycarbonyl groups each having about 1 to 6 carbon atoms in the alkoxy moiety, and especially lower alkoxycarbonyl groups each having about 1 to 4 carbon atoms in the alkoxy moiety. As the illustrative acyl group, there maybe mentioned formyl, acetyl, propionyl, butyryl, isobutyryl, valeryl, isovaleryl, and pivaloyl groups, and other acyl groups each having about 1 to 6 carbon atoms.
The substituents R
1
and R
2
may be identical to or different from each other. The substituents R
1
and R
2
in the formula (1) may be combined to form a double bond, or an aromatic or nonaromatic ring. The preferred aromatic or nonaromatic ring is a 5- to 12-membered ring, and especially a 6- to 10-membered ring. It may be a heterocyclic ring or condensed heterocyclic ring, but it is often a hydrocarbon ring. Such rings include, for example, nonaromatic alicyclic rings (e.g., cyclohexane ring and other cycloalkane rings which may have a substituent, cyclohexene ring and other cycloalkene rings which may have a substituent), nonaromatic bridged rings (e.g., 5-norbornene ring and other bridged hydrocarbon rings which may have a substituent), benzene ring, naphthalene ring and other aromatic rings (including condensed rings) which may have a substituent. The ring is composed of an aromatic ring in many instances. The ring may have a substituent such as an alkyl group, a haloalkyl group, a hydroxyl group, an alkoxy group, a carboxyl group, an alkoxycarbonyl group, an acyl group, a nitro group, a cyano group, an amino group, or a halogen atom.
In the formula (1), X represents an oxygen atom or a hydroxyl group, and the bond between the nitrogen atom N and X is a single bond or a double bond.
On R
1
, R
2
, or on the double bond or aromatic or nonaromatic ring formed together by R
1
and R
2
, one or two N-substituted cyclic imido groups indicated in the formula (1) may further be formed. By way of illustration, when R
1
or R
2
is an alkyl group having 2 or more carbon atoms, the N-substituted cyclic imido group may be formed together with adjacent two carbon atoms constituting the alkyl group. Likewise, when R
1
and R
2
are combined to form a double bond, the N-substituted cyclic imido group may be formed together with the double bond. In case that R
1
and R
2
are combined to form an aromatic or nonaromatic ring, the N-substituted cyclic imido group may be formed with adjacent two carbon atoms constituting the aforementioned ring.
Preferred imide compounds include compounds represented by the following formulas:
(whe

Affiliated with

Also associated with

Rating

Method for production of aldehydes does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method for production of aldehydes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for production of aldehydes will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2549039