323,187. Schroeter, G., and Gluschke, A. Aug. 23, 1928. Lactones of hydrogenated polynuclear hydrocarbons are prepared by condensing a-halogenketone of an hydrogenated hydrocarbon or derivative thereof with an alkali malonic ester, subjecting the cyoloketonyl derivative of the malonic ester thus produced to saponification and reduction in either order (if desired, with additional treatment with acid), and finally eliminating carbon dioxide from the resulting lactone-carboxylic acid to form the simple lactone. Alternatively, the carbon dioxide may be split off from the substituted malonic acid, and the keto-acetic acid so obtained then reduced to form the lactone. Alkylated lactones may be prepared by following the above processes and alkylating the cycloketonylmalonic ester on an ester of the lactone-carboxylic acid. The lactones may also be obtained by reducing a cycloketonyl-oxalic acid or ester, and then transforming the resulting cycloalcohol-glycollic acid or ester directly into the oxylactone or into the lactone through the intermediary of the cycloketonyl-acetic acid which results from mineral acid treatment of the glycollic acid. The products, particularly as the form of their alkali and alkaline earth metal salts, possess vermicide properties. According to the examples, (1), the lactone of 5-hydroxytetrahydronaphthalene-6-acetic acid is prepared by treating 6-brom-5-ketotetrahydronaphthalene with sodium malonic acid methyl ester, heating the saponified product to eliminate carbon dioxide, and the resulting 5-ketotetrahydronaphthalene-6-acetic acid then hydrogenated in presence of a nickel catalyst and the product treated with acid; alternatively the ketotetrahydronaphthalene malonic acid is reduced with sodium amalgam and the product treated with acid, whereby 5- hydroxytetrahydronaphthalene - 6 - acetic - lactone-carboxylic acid is obtained, from which the lactone of 5-hydroxytetrahydronaphthalene-6- acetic acid results on elimination of carbon dioxide; reference is made to the preparation of homologues of the lactones, e.g. the lactone of 5-hydroxytetrahydronaphthalene-6-propionic acid; (2) 1-methoxy-5-ketotetrahydronaphthalene (prepared by catalytic reduction of 1 : 5-dihydroxynaphthalene, and methylation of the product) is brominated, the resulting 6-bromo compound treated with sodium malonic ester and saponified; reduction and treatment with acid of the 1-methoxy-5-ketotetrahydronaphthalene-6-malonic acid yields the lactone of 1-methoxy-5-hydroxytetrahydronaphthalene-6-acetic-carboxylic acid, from which the lactone of 1-methoxy-5-hydroxytetrahydronaphthalene-6-acetic acid is formed by elimination of carbon dioxide; alternatively, carbon dioxide may first be removed from the 1-methoxy-5-ketotetrahydronaphthalene-6-malonic acid and the resulting 1-methoxy-5-ketotetrahydronaphthalene-6-acetic acid converted by reduction and treatment with acid into the lactone of 1 - methoxy-5-hydroxy-tetrahydronaphthalene- 6-acetic acid; (3) the lactone of 1 : 4-dimethyl-5- hydroxytetrahydronaphthalene-6-acetic acid is obtained by treating 1 : 4-dimethyl-5-keto-6- brom-tetrahydronaphthalene with sodium malonic ester, saponifying the product and reducing it to the 1: 4-dimethyl-5-oxytetrahydronaphthalene-6- acetic-lactone-carboxylic acid, and then eliminating carbon dioxide; the corresponding lactone of 1 : 4-dimethyl-5-hydroxytetrahydronaphthalene-6- propionic acid (racemic hyposantonine) is formed by treating the sodium compound of an ester of the lactone-carboxylic acid with ethvl bromide, saponifying the resulting 1 4-dimethyl-5- hydroxytetrahydronaphthalene - 6 - isosuccinic - lactonic ester, eliminating carbon dioxide and finally reforming the lactone ring, which has been opened by the saponification, bv treatment with acid; (4) 1-keto-2-bromo-1 : 2 : 3 : 4 : 5 : 6 : : 7 : 8-octohydroanthracene is condensed with sodium malonic ester, and carbon dioxide eliminated from the saponified product to give 1-keto-octohydroanthracene-2-acetic acid, which, on reduction and treatment with acid, yields the lactone of 1-hydroxyoctohydroanthracene-2-acetic acid; (5) a lactone is prepared in the foregoing manner from 3-hydroxy-5-ketotetrahydronaphthalene-6- acetic acid, which is obtained by nitrating 5-ketotetrahydronaphthalene-6-acetic acid reducing the 3-nitro product with ferrous sulphate and ammonia to the amino compound and converting the latter into the hydroxy body; (6) 5-ketotetrahydronaphthalene-6-oxalic ethyl ester is saponified, reduced with sodium amalgam to the stereoisomeric 5-hydroxytetrahydronaphthalene-6- glycollic acids, which are then heated with acid to form the lactone of 5-hydroxytet.rahydronaphthalene-6-glycollic acid; the latter is also obtained by treating the 5-hydroxytetrahydronaphthalene- 6-glycollic acid with acetic anhydride and saponifying the resulting lactone of 5-hydroxytetrahydronaphthalene - 6 - acetylglycollic acid; (7) 1- methoxy-5-ketotetrahydronaphthalene is condensed with sodium and oxalic ester, the product saponified and reduced with sodium amalgam to the stereoisomeric 1-methoxy-5-hydroxytetrahydronaphthalene-6-glycollic acids and their lactones; treatment of the mixture with acid gives 1-mebhoxy-5-ketotetrahydronaphthalene-6- acetic acid, which on reduction forms the lactone of 1 - methoxy-5-hydroxytetrahydronaphthalene-6 acetic acid; (8) 1-keto-1 : 2 : 3 : 4 : 5 : 6 : 7 : 8- octohydroanthracene-2-oxalic acid, obtained by treating 1-keto-octohydroanthracene with sodium and oxalic ester, is saponified and the product reduced to 1-hydroxyoctohydroanthracene-2-glycollic acid; heating the latter with acid for a short time produces the lactone of 1-hydroxyoctohydroanthracene-2-glycollic acid, whilst longer treatment gives rise to 1-keto-octohydroanthracene-2- acetic acid. a-Halogen-ketones of hydrogenated polylnuclear hydrocarbons and their derivatives are prepared by oxidizing the hydrogenated hydrocarbon or derivative with chromic acid, with subsequent halogenation. Products from decahydronaphthalenes, tetrahydrophenanthrenes and tetrahydroanthracenes are referred to. Thus, 5-keto-6-bromtetrahydronaphthalene is prepared by brominating the oxidation product of tetrahydronaphthalene, 1 : 4-dimethyl-5-keto-6-brom-tetrahydronaphthalene by oxidizing 1: 4-dimethyl-5 : 6 : 7 : 8- tetrahydronaphthalene and brominating the product, and 1-keto-2-bromo-1 : 2 : 3 : 4 : 5 : 6 : 7 : 8-octohydroanthracene by brominating the oxidation product of octohydroanthracene.