Patent GB-1234281-A (GB)
IPC: C07C51/347
Filed: 1968-05-09
Abstract: 1,234,281. Phenanthrene derivatives. SYNTEX CORP. 9 May, 1968 [15 May, 1967; 25 Sept., 1967], No. 22090/68. Heading C2C. [Also in Divisions A5 and C7] Compounds of the formula (wherein each of Z<SP>1</SP> and Z<SP>2</SP> is a carbon-carbon single or double bond, but Z<SP>1</SP> is a double bond when Z<SP>2</SP> is a double bond; R<SP>1</SP> is H, OH, C 1-6  alkoxy, C 5-6  cycloalkyloxy, tetrahydropyran- 2 - yloxy, tetrahydrofuran - 2 - yloxy or C 1-6  hydrocarbon carboxylic acyloxy; R<SP>2</SP> can have the same values as R<SP>1</SP> or can be C 1-6  alkyl, R<SP>3</SP> is H, CH 3  or C 2 H 5 ; R<SP>4</SP> is H, CH 3 , C 2 H 5 ; C 3 H 7 , phenyl, benzyl, C 1-6  alkoxy or CN; R<SP>5</SP> is H, CH 3 , C 2 H 5  or C 3 H 7 ; and R<SP>6</SP> is H, C 1-6  alkyl, Na or K, and when it is Na or K neither R<SP>1</SP> nor R<SP>2</SP> is acyloxy) are prepared by the following process (wherein Ac is acetyl) (I) can be replaced by a corresponding 1- vinyl - 1 - tetralol, used in the presence of an alkaline catalyst. (III)#(IV) is effected with an acid; (IV)#(V) is dehydrogenation with a Pd catalyst; (IV) or (V)#(VI) is effected with a base in an aqueous water-miscible organic solvent; (VI)#(VIIA) + (VIIB) (tautomeric mixture) is effected with an acid; and the tautomeric mixture is subjected to carbonyl reduction, chemically (e.g. via a hydrazone or a thioketal) or electrolytically, to give (VIII), which, when Z<SP>2</SP> is a single bond, may then be hydrogenated (e.g. with Na/liquid NH 3 ) to the corresponding 4a,10a - dihydro compounds. Groups affected by the acid or base treatments during the process may subsequently be restored, and the free acid products may subsequently be converted to salts or esters thereof. In the conversion of (IV) or (V) to (VI), short reaction times favour the formation of cis products (as shown in the reaction scheme), while long reaction times (over 3 hours) lead to trans products. Cis and trans products may be separated by fractional crystallization. The products of these processes are obtained as dlmixtures which may be resolved by standard procedures. When R<SP>3</SP> is other than H, mixtures of 7α and 7# isomers may be separated by standard procedures at any stage. Specified interconversions of compounds A<SP>1</SP> additional to those mentioned above are: (i) 9,10 - dehydrogenation; (ii) conversion of a trans - isomer to a cis - isomer; (iii) esterification and etherification of OH groups; (iv) hydrolysis of esters; and (v) cleavage of ethers. Novel products, which may be d, l or dl, have the formulµ wherein R is C 1-6  alkoxy, C 5-6  cycloalkyloxy, tetrahydropyran - 2 - yloxy, tetrahydrofuran- 2 - yloxy, C 1-6  hydrocarbon carboxylic acyloxy, hydroxy or the sulphate or phosphate ester thereof; R<SP>1</SP> can have these values and can also be C 1-6  alkyl; R1<SP>11</SP> can have the values of R and can also be H, but when it is not H, R<SP>1</SP> is C 1-6  alkyl; R<SP>31</SP> is methyl or ethyl; and R<SP>3</SP>, R<SP>4</SP>, R<SP>5</SP>, R<SP>6</SP>, Z<SP>1</SP> and Z<SP>2</SP> have the values given above. The sulphate and phosphate esters are prepared conventionally, e.g. using SO 3 -CH 2 NH 2 /py or # - cyanoethyl phosphate/N,N<SP>1</SP> - dicyclohexylcarbodiimide. Most compounds of Formula III comprise the subject-matter of Specification 1,234,282. 6,8 - Diacyloxy - 1 - tetralones and 6 - acyloxy- 1 - tetralones wherein the acyl groups are derived from acetic, propionic, butyric, caproic and trimethylacetic acids are prepared by esterification of the free ols.