Organic compounds -- part of the class 532-570 series – Organic compounds – Amino nitrogen containing
Patent
1997-05-07
1998-09-22
Shippen, Michael L.
Organic compounds -- part of the class 532-570 series
Organic compounds
Amino nitrogen containing
548221, 558232, 558239, 558241, 558252, 558262, 558272, 560142, 564300, C07C27300
Patent
active
058115790
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The present invention relates to a method of synthesizing a 2-substituted nitrogen-containing compound and has particular reference to a method of synthesizing an ortho-substituted aryl compound having a nitrogen-containing group in the 1-position. In one aspect, the present invention comprehends a method of producing an aromatic nitrogen-containing compound having a sulphur-containing moiety in the 2-position.
BACKGROUND OF THE INVENTION
Aromatic sulfur-containing compounds are of great importance in the manufacture of photographic, pharmaceutical and pesticidal materials. For example, in photography, aromatic thiols have been found useful as coupling-off groups when incorporated into couplers. It has been found that 2-acylaminothiols are particularly useful as coupling-off groups in magenta couplers, since they exhibit substantially no leuco-dye problem. Aromatic disulfides are of use as intermediates in coupler synthesis and as light stabilizers for magenta dyes.
EP-A-0 251552 discloses a process for producing aminothiophenols and their derivatives comprising the pyrolytic rearrangement of O-(N-acylaminoaryl)-N,N-di(organo)thiocarbamate. This type of rearrangement reaction is known as the Newman-Kwart rearrangement reaction and is described in J. Org. Chem., 31, 410 (1966) by Messrs. Kwart and Evans and in Org. Synth., 51, 139 (1971) by Messrs. Newman and Hetzel. It is thought that the Newman-Kwart rearrangement reaction proceeds via an unstable 4-member ring intermediate.
PROBLEM TO BE SOLVED BY THE INVENTION
The problem with the use of the Newman-Kwart rearrangement reaction to produce aromatic sulfur containing compounds is that high temperatures are required; this makes the process undesirable for synthesis on an industrial scale. EP-A-0 251552 in Example 8, for example, discloses that the pyrolytic rearrangement of O-(N-acetyl-para-aminophenyl)dimethylthiocarbamate is conducted at 280.degree. C. under nitrogen for 2 hours in sulfolane. The present invention seeks to provide a method for producing e.g. aromatic sulfur-containing compounds at lower temperatures, which is thus more susceptible of industrial application as compared with the Newman-Kwart rearrangement reaction referred to above.
SUMMARY OF THE INVENTION
According to one aspect of the present invention therefore there is provided a method of synthesizing a compound having a general formula (I) as follows: ##STR5## comprising the step of reacting a hydroxylamine of general formula (II): ##STR6## or a nitrone of general formula (III): ##STR7## with a compound of general formula (IV): ##STR8## thereby to form an intermediate compound, and thereafter causing or allowing said intermediate compound to undergo a pericyclic sigmatropic rearrangement reaction to form the compound (I); wherein X is a nucleofugal group, Y is selected from O,S,NH,NR.sub.5 and CR.sub.6 R.sub.7, R.sub.1 is a group which directs the reactivity of compound (II) onto the oxygen atom and R.sub.2 to R.sub.9 are each a substituted or unsubstituted aliphatic, aromatic, heteroaryl or cyclic group or hydrogen which is substantially inert or protected during the reaction.
Said compound (I) may be isolatable; alternatively, in some embodiments, the compound (I) may itself be an intermediate which cannot be isolated. Without wishing to be bound by theory, it is thought that compounds (II) or (III) and (IV) react to form said intermediate compound which is caused or allowed to undergo a pericyclic sigmatropic rearrangement reaction via a pericyclic transition state (V): ##STR9##
It is thought that the nitrogen-oxygen bond in the intermediate compound breaks as the carbon-Y bond forms accompanied by the elimination of a proton.
In a particular aspect of the present invention, Y may be sulfur, in which case it will be seen that the method of the present invention results in a 2-(sulfur containing group) substituted nitrogen-containing compound.
ADVANTAGEOUS EFFECTS OF THE INVENTION
In some embodiments, the rearrangement of said intermediate compou
REFERENCES:
patent: 3567776 (1971-03-01), Krenzer
Eastman Kodak Company
Kluegel Arthur E.
Shippen Michael L.
LandOfFree
Method of synthesizing a 2-substituted nitrogen-containing compo 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 of synthesizing a 2-substituted nitrogen-containing compo, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of synthesizing a 2-substituted nitrogen-containing compo will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1622959