The present invention provides a process for preparing an 11-halo-3-undecene compound (7) in which X.sup.1 represents a halogen atom, the process comprising a step of subjecting a nucleophilic reagent, 3-hexenyl compound (5): in which M.sup.2 represents Li or MgZ.sup.2, wherein Z.sup.2 represents a halogen atom or a 3-hexenyl group, to a coupling reaction with a 1-halo-5-halopentane compound (6) in which X.sup.3 and X.sup.4 may be same with or different from each other and represent a halogen atom, to produce the 11-halo-3-undecene compound (7). The present invention also provides a process for preparing a 9-dodecenal compound (4): the process comprising a step of subjecting a nucleophilic reagent, 8-undecenyl compound (1) in which M.sup.1 represents Li or MgZ.sup.1, wherein Z.sup.1 represents a halogen atom or an 8-undecenyl group, and an orthoformic ester compound (2) in which R may be same with or different from each other and represents an alkyl group having 1 to 6 carbon atoms, to a nucleophilic substitution reaction to produce a 1,1-dialkoxy-9-dodecene compound (3) in which R are as defined above; and hydrolyzing the 1,1-dialkoxy-9-dodecene compound (3) thus obtained to produce the 9-dodecenal compound (4).

##STR00001##

This invention discloses the first example of palladium(II)-catalyzed -C(sp.sup.3)-H iodination or arylation of a wide range of ketones by using a commercially available aminooxyacetic acid auxiliary. This L, X-type directing group overcomes the limitation of the transient directing group approach for -C(sp.sup.3)-H functionalization of ketones. Practical advantages of this method include simple installation of the auxiliary without chromatography, exceptional tolerance of a-functional groups, double bonds and triple bonds and rapid access to diverse sterically hindered quaternary centers.

This invention discloses the first example of palladium(II)-catalyzed -C(sp.sup.3)-H iodination or arylation of a wide range of ketones by using a commercially available aminooxyacetic acid auxiliary. This L, X-type directing group overcomes the limitation of the transient directing group approach for -C(sp.sup.3)-H functionalization of ketones. Practical advantages of this method include simple installation of the auxiliary without chromatography, exceptional tolerance of a-functional groups, double bonds and triple bonds and rapid access to diverse sterically hindered quaternary centers.

This invention discloses the first example of palladium(II)-catalyzed -C(sp.sup.3)-H iodination or arylation of a wide range of ketones by using a commercially available aminooxyacetic acid auxiliary. This L, X-type directing group overcomes the limitation of the transient directing group approach for -C(sp.sup.3)-H functionalization of ketones. Practical advantages of this method include simple installation of the auxiliary without chromatography, exceptional tolerance of a-functional groups, double bonds and triple bonds and rapid access to diverse sterically hindered quaternary centers.

The object of the present invention is to provide a process for preparing a 5-alken-1-yne compound efficiently at low costs and a process for preparing (2E,6Z)-2,6-nonadienal by making use of the aforesaid process for preparing the 5-alken-1-yne compound. There is provided a process for preparing a 5-alken-1-yne compound of the following formula (4): YZCR.sup.1CR.sup.2(CH.sub.2).sub.2CCH (4) in which Y in formula (4) represents a hydrogen atom or a hydroxyl group, the process comprising at least steps of: subjecting (i) an alkenylmagnesium halide compound prepared from a haloalkene compound of the following formula (1): YZCR.sup.1CR.sup.2(CH.sub.2).sub.2X.sup.1 (1) and (ii) an alkyne compound of the following formula (2): X.sup.2CCSi(R.sup.3)(R.sup.4)(R.sup.5) (2) to a coupling reaction to form a silane compound of the following formula (3): YZCR.sup.1CR.sup.2(CH.sub.2).sub.2CCSi(R.sup.3)(R.sup.4)(R.sup.5) (3); and subjecting the silane compound (3) to a desilylation reaction to form the 5-alken-1-yne compound (4).

The object of the present invention is to provide a process for preparing a 5-alken-1-yne compound efficiently at low costs and a process for preparing (2E,6Z)-2,6-nonadienal by making use of the aforesaid process for preparing the 5-alken-1-yne compound. There is provided a process for preparing a 5-alken-1-yne compound of the following formula (4): YZCR.sup.1CR.sup.2(CH.sub.2).sub.2CCH (4) in which Y in formula (4) represents a hydrogen atom or a hydroxyl group, the process comprising at least steps of: subjecting (i) an alkenylmagnesium halide compound prepared from a haloalkene compound of the following formula (1): YZCR.sup.1CR.sup.2(CH.sub.2).sub.2X.sup.1 (1) and (ii) an alkyne compound of the following formula (2): X.sup.2CCSi(R.sup.3)(R.sup.4)(R.sup.5) (2) to a coupling reaction to form a silane compound of the following formula (3): YZCR.sup.1CR.sup.2(CH.sub.2).sub.2CCSi(R.sup.3)(R.sup.4)(R.sup.5) (3); and subjecting the silane compound (3) to a desilylation reaction to form the 5-alken-1-yne compound (4).

This invention discloses the first example of palladium(II)-catalyzed -C(sp.sup.3)-H iodination or arylation of a wide range of ketones by using a commercially available aminooxyacetic acid auxiliary. This L, X-type directing group overcomes the limitation of the transient directing group approach for -C(sp.sup.3)-H functionalization of ketones. Practical advantages of this method include simple installation of the auxiliary without chromatography, exceptional tolerance of a-functional groups, double bonds and triple bonds and rapid access to diverse sterically hindered quaternary centers.

This invention discloses the first example of palladium(II)-catalyzed -C(sp.sup.3)-H iodination or arylation of a wide range of ketones by using a commercially available aminooxyacetic acid auxiliary. This L, X-type directing group overcomes the limitation of the transient directing group approach for -C(sp.sup.3)-H functionalization of ketones. Practical advantages of this method include simple installation of the auxiliary without chromatography, exceptional tolerance of a-functional groups, double bonds and triple bonds and rapid access to diverse sterically hindered quaternary centers.

This invention discloses the first example of palladium(II)-catalyzed -C(sp.sup.3)-H iodination or arylation of a wide range of ketones by using a commercially available aminooxyacetic acid auxiliary. This L, X-type directing group overcomes the limitation of the transient directing group approach for -C(sp.sup.3)-H functionalization of ketones. Practical advantages of this method include simple installation of the auxiliary without chromatography, exceptional tolerance of a-functional groups, double bonds and triple bonds and rapid access to diverse sterically hindered quaternary centers.

There are provided methods of efficiently producing compounds that are, for example, sex pheromones of San Jose Scale. For example, there is provided a method for producing a 7-methyl-3-methylene-7-octenyl carboxylate compound (4), the method including the steps of: hydrolyzing a 7-methyl-3-methylene-7-octenal acetal compound (1) to obtain 7-methyl-3-methylene-7-octenal (2); reducing the 7-methyl-3-methylene-7-octenal (2) to obtain 7-methyl-3-methylene-7-octenol (3); and esterifying the 7-methyl-3-methylene-7-octenol (3) to obtain a 7-methyl-3-methylene-7-octenyl carboxylate compound (4).

##STR00001##