A built-in micro interfacial enhanced reaction system and process for PTA production with PX are provided. The system includes a reactor and a micro interfacial unit disposed inside reactor. The reactor includes a shell, an inner cylinder concentrically disposed inside shell, and a circulating heat exchange device partially disposed outside shell, inner cylinder having a bottom end connected to inner bottom surface of the shell in closed manner and an open top end, a region between shell and inner cylinder being first reaction zone, inner cylinder containing second reaction zone and third reaction zone from top to bottom, circulating heat exchange device being connected to inner cylinder and micro interfacial unit respectively. The invention can solve problems of large waste of reaction solvent acetic acid under high temperature and high pressure and being unable to take out the product TA in time during existing process of PTA production with PX.

A built-in micro interfacial enhanced reaction system and process for PTA production with PX are provided. The system includes a reactor and a micro interfacial unit disposed inside reactor. The reactor includes a shell, an inner cylinder concentrically disposed inside shell, and a circulating heat exchange device partially disposed outside shell, inner cylinder having a bottom end connected to inner bottom surface of the shell in closed manner and an open top end, a region between shell and inner cylinder being first reaction zone, inner cylinder containing second reaction zone and third reaction zone from top to bottom, circulating heat exchange device being connected to inner cylinder and micro interfacial unit respectively. The invention can solve problems of large waste of reaction solvent acetic acid under high temperature and high pressure and being unable to take out the product TA in time during existing process of PTA production with PX.

The regio-selective functionalization of a dialkyl benzene compound ##STR00001##
wherein the ratio of the compound functionalized at position (a) to the compound functionalized at the position (b) is at least 70:30, more particularly at least 80:20, still more particularly at least 85:15, and still more particularly at least 90:10, characterised in that the substituent R is an isobutyl group.

The regio-selective functionalization of a dialkyl benzene compound ##STR00001##
wherein the ratio of the compound functionalized at position (a) to the compound functionalized at the position (b) is at least 70:30, more particularly at least 80:20, still more particularly at least 85:15, and still more particularly at least 90:10, characterised in that the substituent R is an isobutyl group.

A compound is provided of Formula (I) ##STR00001##
wherein R.sup.1 represents a C.sub.3 to C.sub.20 hydrocarbon group derived from an alcohol of formula R.sup.1OH, from a formate of formula R.sup.1OCHO, or a cinnamyl aldehyde of Formula (II) ##STR00002##
wherein a compound of Formula I is capable of releasing a compound, when oxidized, selected from the group consisting of a fragrant alcohol of formula R.sup.1OH, a fragrant formate ester of formula R.sup.1OCHO and aryl aldehyde of Formula (III) ##STR00003##
wherein R.sup.2 is, independently, hydrogen atom, hydroxyl group, optionally substituted C.sub.1-C.sub.6 alkyl group, C.sub.1-C.sub.6 alkoxy group, or O(CO)CH(CH3).sub.2 wherein any two of R.sup.2 may form an optionally substituted 5 or 6 membered ring. The compounds are useful for example as a precursor for the prolonged delivery or release of fragrant compounds such as fragrant alcohols, fragrant aldehydes or fragrant formates.

A compound is provided of Formula (I) ##STR00001##
wherein R.sup.1 represents a C.sub.3 to C.sub.20 hydrocarbon group derived from an alcohol of formula R.sup.1OH, from a formate of formula R.sup.1OCHO, or a cinnamyl aldehyde of Formula (II) ##STR00002##
wherein a compound of Formula I is capable of releasing a compound, when oxidized, selected from the group consisting of a fragrant alcohol of formula R.sup.1OH, a fragrant formate ester of formula R.sup.1OCHO and aryl aldehyde of Formula (III) ##STR00003##
wherein R.sup.2 is, independently, hydrogen atom, hydroxyl group, optionally substituted C.sub.1-C.sub.6 alkyl group, C.sub.1-C.sub.6 alkoxy group, or O(CO)CH(CH3).sub.2 wherein any two of R.sup.2 may form an optionally substituted 5 or 6 membered ring. The compounds are useful for example as a precursor for the prolonged delivery or release of fragrant compounds such as fragrant alcohols, fragrant aldehydes or fragrant formates.

A catalyst includes a carrier, and a metal obtained by reducing a metal ion supported on the carrier 1) in a supercritical state or 2) in a polar organic solvent, wherein the carrier is an inorganic porous body having a hierarchical porous structure. By employing the catalyst, it is possible to exhibit better catalytic activity than a conventional catalyst. Heat generation and spontaneous ignition are prevented because no organic porous body is used.

A catalyst includes a carrier, and a metal obtained by reducing a metal ion supported on the carrier 1) in a supercritical state or 2) in a polar organic solvent, wherein the carrier is an inorganic porous body having a hierarchical porous structure. By employing the catalyst, it is possible to exhibit better catalytic activity than a conventional catalyst. Heat generation and spontaneous ignition are prevented because no organic porous body is used.

An object of the present invention is to provide a method for producing 2,4-dialkylbenzaldehyde with excellent conversion rate and yield, and excellent regioselectivity for formylation, by allowing carbon monoxide to react on a starting material containing a specific m-dialkylbenzene in the presence of hydrogen fluoride and boron trifluoride. The method for producing 2,4-dialkylbenzaldehyde according to the present invention comprises a step of allowing carbon monoxide to react on a starting material containing m-dialkylbenzene represented by formula (1) in the presence of hydrogen fluoride and boron trifluoride for formylation at least at a position (a), wherein the starting material is a dialkylbenzene containing more than 90 mol % of m-dialkylbenzene represented by formula (1), and the number of moles of boron trifluoride relative to 1 mole of m-dialkylbenzene represented by formula (1) is 0.7 mol or more and 3.0 mol or less:

##STR00001## a wherein R.sup.1 represents an alkyl group having 1 or more and 3 or less carbon atoms, and R.sup.2represents a chain or cyclic alkyl group having 2 or more and 7 or less carbon atoms, with a secondary or tertiary carbon at the benzylic position, provided that the number of carbons of R.sup.2 is larger than the number of carbons of R.sup.1.

An object of the present invention is to provide a method for producing 2,4-dialkylbenzaldehyde with excellent conversion rate and yield, and excellent regioselectivity for formylation, by allowing carbon monoxide to react on a starting material containing a specific m-dialkylbenzene in the presence of hydrogen fluoride and boron trifluoride. The method for producing 2,4-dialkylbenzaldehyde according to the present invention comprises a step of allowing carbon monoxide to react on a starting material containing m-dialkylbenzene represented by formula (1) in the presence of hydrogen fluoride and boron trifluoride for formylation at least at a position (a), wherein the starting material is a dialkylbenzene containing more than 90 mol % of m-dialkylbenzene represented by formula (1), and the number of moles of boron trifluoride relative to 1 mole of m-dialkylbenzene represented by formula (1) is 0.7 mol or more and 3.0 mol or less:

##STR00001## a wherein R.sup.1 represents an alkyl group having 1 or more and 3 or less carbon atoms, and R.sup.2represents a chain or cyclic alkyl group having 2 or more and 7 or less carbon atoms, with a secondary or tertiary carbon at the benzylic position, provided that the number of carbons of R.sup.2 is larger than the number of carbons of R.sup.1.