Patent GB-1251129-A (GB)
IPC: C07C62/32
Filed: 1969-02-12
Abstract: 1,251,129. 13,14 - Seco - 1,2,3,4 - tetrahydrophenanthrenes. SYNTEX CORP. 12 Feb., 1969 [18 March, 1968], No. 7614/69. Heading C2C. The invention comprises 13,14-seco - l,2,3,4- tetrahydrophenanthrenes of the Formula (A): where R is H, carboxylic acyloxy, C 1-6  alkoxy, cyclopentyloxy, cyclohexyloxy, tetrahydropyran - 2<SP>1</SP>- yloxy or tetrahydrofuran - 2<SP>1</SP> - yloxy ; R<SP>1</SP> is CH 3  or C 2 H 5 ; R<SP>2</SP> is -CHO, -CH 2 OR<SP>4</SP> or -COOR<SP>5</SP>, in which R<SP>4</SP> is H, C 1-6  alkyl or carboxylic acyl, and R<SP>5</SP> is H, C 1-6  alkyl, alkali metal or alkaline earth metal; R 3  is CH 3  or C 2 H 5 ; and X is -CH 2 -, -CF 2 -, -CCl 2 - or -O-. Compounds wherein R is H and R<SP>2</SP> is -CH 2 OH or -COOH can be obtained by the reaction sequence wherein (I) is reduced to (II) by treatment with alkali metal in an alcohol; (II) is reacted with a per acid to form (III), where X is oxa, or with a dihalocarbene to form (III), where X is -CF 2 - or -CCl 2 -; the latter can be treated with Na or Li in liquid NH 3  in the presence of alkanol to form (III), where X is -CH 2 -; (III) in converted to (IV) by treatment with Br 2  in an inert organic solvent and (IV) is treated with a base in an organic solvent to yield (V). Compounds of Formula A where R is other than H can be obtained by the sequence. where R<SP>1</SP> is C 1-6  alkyl, R<SP>11</SP> is C 1-6  alkyl, cyclopentyl, cyclohexyl, carboxylic acyl, tetrahydropyran - 21 - yl or tetrahydrofuran - 2<SP>1 </SP>- yl and X<SP>1</SP> is -CH 2 -, -CF 2 - or -CCl 2 -, where (I<SP>1</SP>) is reduced with alkali metal and liquid NH 3  to (II<SP>1</SP>) which on treatment with a weak acid yields (III<SP>1</SP>); the latter is reduced to (IV<SP>1</SP>) which is converted to X = -CF 2 -, -CCl 2  or -CH 2 - derivatives (V<SP>1</SP>) as above; (V<SP>1</SP>) is oxidized with CrO 3  in pyridine to (VI) which is converted to (VIII) with SeO 2 ; or VI is treated with CuBr to give (VII) which is dehydrobrominated to (VIII); (VIII) is treated with a carboxylic acid anhydride to give IX (R<SP>11</SP> is acyl); or (VIII) is reacted with a C 1-6  alkanol or cycloalkanol to give IX (R<SP>11</SP> is alkyl or cycloalkyi); IX is treated with a Pd catalyst, 2,3- dichloro-5,6-dicyano-1,4-benzoquinone or N- bromosuccinimide to give (X). Compounds of Formula A where X is oxa and R is other than H are obtained by the sequence: (VI<SP>1</SP>) is treated with CuBr to form (VII<SP>1</SP>); the latter is treated with Zn to form a Zn enolate and then with (a) a carboxylic anhydride to give (VIII<SP>1</SP>) where R<SP>11</SP> is acyi or (b) a dialkyl or dicycloalkyl sulphate to give (VIII<SP>1</SP>), where R<SP>11</SP> is C 1-6  alkyl or cycloalkyl, or (c) tetrahydropyranyl or tetrahydrofuranyl halide to form the corresponding (V111<SP>1</SP>); (VIII<SP>1</SP>) is then brominated, e.g. with N-bromosuccinimide, forming (IX<SP>!</SP>) which is dehydrobrominated by treatment with pyridine or other weak base to form (X<SP>1</SP>). Compounds of Formula A, where R<SP>2</SP> is -COO alkyl, -CH 2 OH or -CHO can be obtained from (A; R 2  is COOH) by conventional methods. Pesticidal compositions for control of rodents (by reason of anti-fertility activity) comprise a compound of Formula A above together with a bait or carrier.