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(wherein R is a hydrogen atom or a lower alkyl group, e.g. methyl, ethyl, propyl, butyl; R’ and R" are the same or different and each is a •hydrogen atom or a lower alkoxy group, e.g. methoxy, ethoxy, propoxy; X is an organic acid residue, e.g. p-toluenesulfonyl group; and Y is a lower alkyl group, e.g. methyl, ethyl, propyl) 

The starting compounds (I) are novel ones and may be prepared by reacting a 3-cyclohexene-1-methylamine (XI) with lead tetraacetate. 

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The :first step consists of two stages and the former stage is carried out by reacting a compound CI) with a compound (H), if necessary, in a suitable amount of anhydrous organic solvent to ,give an ester intermediate of the compound (III).. As organic solvent, inert solvents inactive to the reactive compounds, i.e. the compound (:[) and the compound (II), for example, an alcohol (e.g. methanol, ethanol), t-butanol, an ether (e.g. diethyl ether, tetrahydrofuran, dioxane, diglyme), a ketone ( e.g. ace› tone, methyl ethyl ketone), an amine (e.g. pyridine, pico› line ), dimethylsulfoxide, N,N-dimethylformarnide, ace› tonitrile, dichloromethane, chloroform, or the like, may optionally be used. The reaction proceeds readily without specially heating, and may be carried out in the wide range of temperature, such as the ice-cooling temperature to the refluxing temperature of the reaction medium. The reaction period is about one hour or a few days, which may be varied according to the reaction conditions. 

In the latter stage of the first step, the resulting ester derivatives are hydrolyzed according to the conventional procedure of hydrolysis of an organic acid ester with an alkali, e.g. an alkali metal hydroxide such as sodium hy› droxide, potassium hydroxide, or a carbonate such as sodium carbonate, sodium bicarbonate, potassium carbon› ate, potassium bicarbonate. 

In the second step, the resulting compounds (III) are oxidized to the corresponding ketones (IV). The oxida› tion may be achieved by applying the oxidizing method or reagent for converting secondary alcohols to ketones such as N-bromosuccinimide, Oppenauer method, dimeth› ylsulfoxide-acetic anhydride, dimethylsulfoxide-dicyclo› hexylcarbodiimide (DCC), or the like. 

In the third step, the resulting compounds (IV) are sub› jected to intramolecular cyclization together with acyla› tion by interacting an organic acid. In this case, the reac› tion proceeds stereospecifically and smoothly and affords 

(I). 

the objective cyclic ester derivatives (V) in good yield. The reaction is carried out at an optional temperature, ranging from room temperature to the refluxing tempera› ture of the reaction medium, and completed within sev› eral minutes to several hours. As solvent, as far as unaf› fecting the main reaction, the optional solvents may be used, and particularly aprotic solvents such as hydrocar› bon solvents, e.g. benzene, toluene, ether solvents, e.g. diethyl ether, tetrahydrofuran, dioxane, or acetonitrile, or protic solvents such as acetic acid, may be used. As or› ganic acid, most acids, not accompanied by steric hin› drance by bulky group; may be used, and in general the acids having the small pKa value are more preferable. In view of this point sulfonic acids, e.g. p-toluenesulfonic acid, methanesulfonic acid, bromobenzenesulfonic acid, are the most advantageous. In this reaction the acid resi- due X arising from the acid used is introduced into the compounds (V). 

In the fourth step, the XO-group in the compounds (V) is displaced by the YO-group by a lower alcohol. The solvolysis is carried out by reacting the compound (V) with a lower alcohol in the presence of an acid catalyst such as a mineral acid, e.g. hydrochloric acid, sulfuric acid, or an organic acid, e.g. p-toluenesulfonic acid, or a base catalyst such as an alkali metal hydroxide, e.g. sodi› um hydroxide, potassium hydroxide, a metal alkoxide, e.g. sodium methoxide, potassium methoxide, sodium eth› oxide, potassium ethoxide, potassium t-butoxide, or a complex metal hydride, e.g. sodium borohydride, potas› sium boroliydride, at a temperature ranging from room temperature to the refluxing temperature of the reaction medium for several hours or several days. Lower alkanols used in the solvolysis are methanol, ethanol, propanol, or the like. In order to avoid the side reaction such as isom› erization; the reaction is preferably carried out in basic medium at low temperature as mildly as possible. In this case, the lower alkyl group Y arising from the alcohol used ( or alkoxy group when used alkoxide) is introduced into the compounds (VI). 

In the fifth step, the lactam ring in the resulting ether derivatives (VI) is reduced with a metal hydride. The complex metal hydrides used in this step are lithium alu› minum hydride, lithium diethoxy aluminum hydride, lithium triethoxy aluminum hydride, lithium tri-t-butoxy aluminum hydride, lithium borohydride, or the like. In general the reduction of lactam with metal hydride, e.g. lithium aluminum hydride, directly affords a desoxy deriv› ative (corresponding to the compound VIII), however, in this reaction affords intermediately a carbinol amine, which is farther dehydrated to a vinyl amine (if neces› sary with alumina or phosphorus oxychloride-pyridine; on the contrary, the reduction with an aluminum hydride, e.g. 

