The invention relates to a method of producing carbonyl compounds, more particularly C.sub.2-C.sub.4 ketones and aldehydes. The method is based on the gas-phase oxidation by nitrous oxide of C.sub.2-C.sub.4 alkane-olefin mixtures, such as a butane-butylene fraction or a propane-propylene fraction, obtained by thermal and/or catalytic cracking, to produce C.sub.2-C.sub.4 ketones and aldehydes. The process is carried out under continuous flow conditions at a temperature of 300-550° C. and pressure of 1-100 atm, without prior isolation of individual olefins from the fractionation products and in the absence of a catalyst. The process provides for high productivity, high overall selectivity for ketones and aldehydes, and explosion-safe operation.

The invention relates to a method of producing carbonyl compounds, more particularly C.sub.2-C.sub.4 ketones and aldehydes. The method is based on the gas-phase oxidation by nitrous oxide of C.sub.2-C.sub.4 alkane-olefin mixtures, such as a butane-butylene fraction or a propane-propylene fraction, obtained by thermal and/or catalytic cracking, to produce C.sub.2-C.sub.4 ketones and aldehydes. The process is carried out under continuous flow conditions at a temperature of 300-550° C. and pressure of 1-100 atm, without prior isolation of individual olefins from the fractionation products and in the absence of a catalyst. The process provides for high productivity, high overall selectivity for ketones and aldehydes, and explosion-safe operation.

The present invention provides a process for preparing a terminal conjugated alkadienal compound of the following general formula (5):
CH.sub.2═CHCH═CH(CH.sub.2).sub.aCHO   (5)
wherein “a” represents an integer of 1 to 15, from a dialkoxyalkenyl alkoxymethyl ether compound of the following general formula (1):
R.sup.1CH.sub.2OCH.sub.2OCH.sub.2CH.sub.2CH═CH(CH.sub.2).sub.aCH(OR.sup.2)(OR.sup.3)   (1)
wherein R.sup.1 represents a hydrogen atom, an n-alkyl group having 1 to 9 carbon atoms, or a phenyl group, R.sup.2 and R.sup.3 represent, independently of each other, a monovalent hydrocarbon group having 1 to 15 carbon atoms, or R.sup.2 and R.sup.3 may form together a divalent hydrocarbon group, R.sup.2-R.sup.3, having 2 to 10 carbon atoms, and “a” is as defined above.

An aryl-substituted alkanal compound having a molecular weight of less than 300 g/mol and which bears a substituent on the aryl ring ortho to a substituent bearing the aldehyde functionality. Said compounds are useful as perfume ingredients in personal care and household care products.

A compound represented by the formula 1 ##STR00001## wherein R.sub.1 is H, or when R.sub.2 and R.sub.3 is H, then R.sub.1 is CHR.sub.5CHR.sub.6CHO, CR.sub.5CR.sub.6CHO or C(CH.sub.3)CHO, wherein R.sub.5, R.sub.6 each independently may represent H or methyl; R.sub.2 is H, or when R.sub.1 and R.sub.3 is H, then R.sub.2 is CHR.sub.5CHR.sub.6CHO, CR.sub.5CR.sub.6CHO or C(CH.sub.3)CHO, wherein R.sub.5, R.sub.6 each independently may represent H or methyl; R.sub.3 is H, or when R.sub.1 and R.sub.2 is H, then R.sub.3 is CHR.sub.5CHR.sub.6CHO, CR.sub.5CR.sub.6CHO or C(CH.sub.3)CHO, wherein R.sub.5, R.sub.6 each independently may represent H or methyl; and R.sub.4 is methyl or a branched or linear, saturated or unsaturated, unsubstituted or substituted (optionally with cyclopropyl groups), C.sub.2-C.sub.7 alkyl or alkenyl residue, preferentially isobutyl, isoamyl. Said compounds are useful as perfume ingredients in personal care and household care products.

There is provided a method for producing hydroxypivalaldehyde (HPA), including steps (i) to (iii) below in this order, Step (i): a reaction step of reacting IBAL with FA to produce a reaction solution containing HPA, step (ii): an extraction step of extracting the reaction solution with an aldehyde solvent represented by formula (1) under basicity to obtain an extract containing HPA, and step (iii): a distillation and collection step of distilling the extract and then collecting HPA from the residue, ##STR00001## wherein R represents a saturated alkyl group having 3 or more and 7 or less carbon atoms, further wherein the distillation step of the step (iii) is a step of distilling an extract in the presence of water, and an amount of the water which is subjected to the distillation is 100 parts by mass or more and 2,000 parts by mass or less with respect to a total amount, 100 parts by mass, of isobutyraldehyde (IBAL) derived from a raw material and an aldehyde solvent represented by formula (1) in an extract which is subjected to the distillation. The method enables HPA to be mass-produced and the collecting ratio of HPA to be improved while selectively removing impurities other than water contained in HPA, specifically IBAL and the like. According to the method for producing HPA as mentioned above, it is possible to reduce the content of neopentyl glycol-isobutyrate, isobutylaldehyde-hydroxypivalaldehyde-acetal, and isobutylaldehyde-hydroxypivalaldehyde-aldol as specific impurities byproduced from HPA.

A fragrance precursor of 3-(4-isobutyl-2-methyl phenyl)propanal, comprising at least an enamine and/or an aminal as reaction product of 3-(4-isobutyl-2-methylphenyl)propanal (compound according to formula (I)) and a primary and/or secondary amine ##STR00001##
useful as a perfume ingredient.

An aryl-substituted alkanal compound having a molecular weight of less than 300 g/mol and which bears a substituent on the aryl ring ortho to a substituent bearing the aldehyde functionality. Said compounds are useful as perfume ingredients in personal care and household care products.

The invention relates to a method of producing carbonyl compounds, more particularly C.sub.2-C.sub.4 ketones and aldehydes. The method is based on the gas-phase oxidation by nitrous oxide of C.sub.2-C.sub.4 alkane-olefin mixtures, such as a butane-butylene fraction or a propane-propylene fraction, obtained by thermal and/or catalytic cracking, to produce C.sub.2-C.sub.4 ketones and aldehydes. The process is carried out under continuous flow conditions at a temperature of 300-550 C. and pressure of 1-100 atm, without prior isolation of individual olefins from the fractionation products and in the absence of a catalyst. The process provides for high productivity, high overall selectivity for ketones and aldehydes, and explosion-safe operation.

The invention relates to a method of producing carbonyl compounds, more particularly C.sub.2-C.sub.4 ketones and aldehydes. The method is based on the gas-phase oxidation by nitrous oxide of C.sub.2-C.sub.4 alkane-olefin mixtures, such as a butane-butylene fraction or a propane-propylene fraction, obtained by thermal and/or catalytic cracking, to produce C.sub.2-C.sub.4 ketones and aldehydes. The process is carried out under continuous flow conditions at a temperature of 300-550 C. and pressure of 1-100 atm, without prior isolation of individual olefins from the fractionation products and in the absence of a catalyst. The process provides for high productivity, high overall selectivity for ketones and aldehydes, and explosion-safe operation.