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.

The present invention relates to a visible-light-mediated one-step method for preparing phenol and cyclohexanone from cyclohexylbenzene (CHB). The method specifically comprises: under the irradiation of visible light, and with a hydrogen bromide solution as a catalyst and oxygen as an oxidizing agent, directly oxidizing cyclohexylbenzene in an organic solvent to break a carbon-carbon bond, so as to generate phenol and cyclohexanone. The method avoids such a process in a cyclohexylbenzene method in the prior art that cyclohexylbenzene needs to be first oxidized to obtain cyclohexylbenzene-1-hydroperoxide (1-CHBHP), then the mixture of the oxidation reaction products is treated, and then a cyclohexylbenzene peroxide is decomposed in an acidic condition to obtain phenol and cyclohexanone, and also avoids potential risks caused by the accumulation of peroxides. In addition, the method further has a great number of advantages of the operation being simple, reagents being easily available, reaction conditions being mild, easy control being achievable, the reaction being able to be scaled-up, a good selectivity being obtained, etc.

The present invention relates to a visible-light-mediated one-step method for preparing phenol and cyclohexanone from cyclohexylbenzene (CHB). The method specifically comprises: under the irradiation of visible light, and with a hydrogen bromide solution as a catalyst and oxygen as an oxidizing agent, directly oxidizing cyclohexylbenzene in an organic solvent to break a carbon-carbon bond, so as to generate phenol and cyclohexanone. The method avoids such a process in a cyclohexylbenzene method in the prior art that cyclohexylbenzene needs to be first oxidized to obtain cyclohexylbenzene-1-hydroperoxide (1-CHBHP), then the mixture of the oxidation reaction products is treated, and then a cyclohexylbenzene peroxide is decomposed in an acidic condition to obtain phenol and cyclohexanone, and also avoids potential risks caused by the accumulation of peroxides. In addition, the method further has a great number of advantages of the operation being simple, reagents being easily available, reaction conditions being mild, easy control being achievable, the reaction being able to be scaled-up, a good selectivity being obtained, etc.

A metal oxide supported palladium catalyst comprised of a -Bi.sub.2O.sub.3/Bi.sub.2Sn.sub.2O.sub.7 hetero-junction catalyst support and palladium was developed. The catalyst was synthesized using a sol-gel technique as a nanocrystalline structure. In the presence of fluorene, an oxidant and ultraviolet irradiation, the catalyst converts the hydrocarbon to a mixture of fluorenol/fluorenone oxidation products. The close proximity between -Bi.sub.2O.sub.3 and Bi.sub.2Sn.sub.2O.sub.7 heterojunction phases in the catalyst is thought to be responsible for the efficient charge separation and catalytic activity. An indirect chemical probe method using active species scavengers elucidated that the photo-oxidation mechanism proceeds via holes and superoxide radical (O.sub.2..sup.) moieties.

A metal oxide supported palladium catalyst comprised of a -Bi.sub.2O.sub.3/Bi.sub.2Sn.sub.2O.sub.7 hetero-junction catalyst support and palladium was developed. The catalyst was synthesized using a sol-gel technique as a nanocrystalline structure. In the presence of fluorene, an oxidant and ultraviolet irradiation, the catalyst converts the hydrocarbon to a mixture of fluorenol/fluorenone oxidation products. The close proximity between -Bi.sub.2O.sub.3 and Bi.sub.2Sn.sub.2O.sub.7 heterojunction phases in the catalyst is thought to be responsible for the efficient charge separation and catalytic activity. An indirect chemical probe method using active species scavengers elucidated that the photo-oxidation mechanism proceeds via holes and superoxide radical (O.sub.2..sup.) moieties.

A metal oxide supported palladium catalyst comprised of a -Bi.sub.2O.sub.3/Bi.sub.2Sn.sub.2O.sub.7 hetero-junction catalyst support and palladium was developed. The catalyst was synthesized using a sol-gel technique as a nanocrystalline structure. In the presence of fluorene, an oxidant and ultraviolet irradiation, the catalyst converts the hydrocarbon to a mixture of fluorenol/fluorenone oxidation products. The close proximity between -Bi.sub.2O.sub.3 and Bi.sub.2Sn.sub.2O.sub.7 heterojunction phases in the catalyst is thought to be responsible for the efficient charge separation and catalytic activity. An indirect chemical probe method using active species scavengers elucidated that the photo-oxidation mechanism proceeds via holes and superoxide radical (O.sub.2..sup.) moieties.

Provided is a method for producing fluorenone comprising an oxidation step of oxidizing fluorene in the presence of an aliphatic carboxylic acid having 2 to 3 carbon atoms, a metal catalyst, a bromine compound, and oxygen, a solvent removal step of removing the aliphatic carboxylic acid, a heating step at 120 to 350 C., and a distillation step in the order indicated.

Provided is a method for producing fluorenone comprising an oxidation step of oxidizing fluorene in the presence of an aliphatic carboxylic acid having 2 to 3 carbon atoms, a metal catalyst, a bromine compound, and oxygen, a solvent removal step of removing the aliphatic carboxylic acid, a heating step at 120 to 350 C., and a distillation step in the order indicated.

Provided is a method for producing fluorenone comprising an oxidation step of oxidizing fluorene in the presence of an aliphatic carboxylic acid having 2 to 3 carbon atoms, a metal catalyst, a bromine compound, and oxygen, a solvent removal step of removing the aliphatic carboxylic acid, a heating step at 120 to 350 C., and a distillation step in the order indicated.