Patent ES-353910-A1 (ES)
Title: Novel phenanthrene-2-carboxylic acids and derivatives thereof
IPC: C07C51/347
Filed: 1968-05-14
Abstract: Compounds of the formula (wherein each of Z1 and Z2 is a carbon-carbon single or double bond, but Z1 is a double bond when Z2 is a double bond R1 is H, OH, C 1-6 alkoxy, C 5-6 cycloalkyloxy, tetrahydropyran- 2 - yloxy, tetrahydrofuran - 2 - yloxy or C 1-6 hydrocarbon carboxylic acyloxy R2 can have the same values as R1 or can be C 1-6 alkyl, R3 is H, CH 3 or C 2 H 5 R4 is H, CH 3 , C 2 H 5 C 3 H 7 , phenyl, benzyl, C 1-6 alkoxy or CN R5 is H, CH 3 , C 2 H 5 or C 3 H 7 and R6 is H, C 1-6 alkyl, Na or K, and when it is Na or K neither R1 nor R2 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 Z2 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 R3 is other than H, mixtures of 7[alpha] and 7# isomers may be separated by standard procedures at any stage. Specified interconversions of compounds A1 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 formul[mu] 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 R1 can have these values and can also be C 1-6 alkyl R111 can have the values of R and can also be H, but when it is not H, R1 is C 1-6 alkyl R31 is methyl or ethyl and R3, R4, R5, R6, Z1 and Z2 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,N1 - 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.