摘要:
Process for the preparation of (2,2)-paracyclophane or derivatives thereof by the Hofmann elimination of p.-methylbenzyltrimethylammonium hydroxide or derivatives thereof, in an aqueous solution of an alkali metal hydroxide, wherein said elimination is carried out in the presence of a ketone of the formula:Ch.sub.3 --CO--CH.sub.2 --R (I)wherein R is hydrogen, a halogen, or an alkyl-carboxylic group.
摘要:
A process for the preparation of (2,2)-paracyclophane by conversion of p.methylbenzyltrimethylammonium halide to the corresponding hydroxide and by Hofmann elimination from p.methylbenzyltrimethylammonium hydroxide, wherein both reactions are carried out in the same aqueous solution of an alkaline hydroxide and in the presence of a copper or iron compound.
摘要:
A process for the chlorination of the benzene rings of tricyclo 8.2.2.2 hexadeca 4,6,10,12,13,15 hexane (or (2,2)-paracyclophane) having the formula (I): ##STR1## by gaseous chlorine, by operating in the presence of at least one metal chloride as a catalyst, and at least one co-catalyst having the formula V:R--OH (V)whereinR=hydrocarbon or alkylcarboxylic radical with linear or branched chain, containing from 1 to 6 carbon atoms is taught.
摘要:
Process for the alkylation of phenols comprising reacting a phenol with a vinyl-aromatic hydrocarbon in the presence of an acidic catalyst and of a solvent.
摘要:
A process for producing a silane or siloxane compound containing at least one cycloalkyl ring by hydrogenation of a corresponding derivative containing at least one aromatic ring in the presence of a Raney nickel catalyst modified with chromium.
摘要:
A process of producing a silanic or siloxanic compound containing at least one cycloalkyl ring by hydrogenation of a corresponding compound containing at least one aromatic ring, in solution, in the presence of a catalyst comprising palladium, supported on active carbon and at a pressure equal to or higher than 10 bar.
摘要:
A process of producing a silanic or siloxanic compound containing at least one cycloalkyl ring by the hydrogenation of a corresponding compound containing at least one aromatic ring, in the presence of a Raney nickel catalyst having a granulometry comprised essentially between 10 and 150 micrometers and a surface area of at least 80 m.sup.2 /g.
摘要:
Process for the preparation of (2,2)-paracyclophane or derivatives thereof by the Hofmann elimination of p-methylbenzyl-trimethylammonium hydroxide or derivatives thereof, in an aqueous solution of an alkali metal hydroxide, wherein said elimination is carried out in the presence of a compound of the formula (I):(R).sub.m --A--(X).sub.n (I)wherein A represents an aromatic group, X an electron donor group, R hydrogen or an alkyl group containing from 1 to 4 carbon atoms, n is an integer from 1 to 6, and m is zero or an integer from 1 up to a value such that the sum m+n is equal to the number of substitutable positions in the aromatic group.
摘要:
A compound having the following general formula (I): ##STR1## where R is a hydrogen atom; a linear or branched C.sub.1 -C.sub.4 alkyl group, unsubstituted or substituted by at least a phenyl group or at least a hydrogen atom; a benzyl group substituted by at least a linear or branched C.sub.1 -C.sub.4 alkyl or alkoxy group or a nitro group; a silyl substituted by at least a linear or branched, unsubstituted or substituted C.sub.1 -C.sub.4 alkyl group; n is 0 or 1; and Y is a radical of formula ##STR2## wherein A is H, OH, Cl, CH.sub.2, CH.sub.2 X, where X is F, Cl, Br, I, OH or OR' and R' is COCH.sub.3 or a linear or branched, unsubstituted or substituted C.sub.1 -C.sub.4 alkyl group and - - - represents a single or a double bond, with the proviso that when n=0 and R is H, R' is not a methyl group.
摘要:
A process is described for preparing 3-exomethylene cephalosporanic acid derivatives for use in the synthesis of cephalosporin antibiotics such as ceftibuten. The process comprises electrochemical reduction of a compound of the formula (IV) ##STR1## wherein: R.sup.3 is CH.sub.3 C(O)--; ##STR2## is an optional sulfoxide group; n is 2 or 3; R.sup.1 is H and R is H or NHR.sup.2, where R.sup.2 is H or a protecting group selected from C.sub.6 H.sub.5 CH.sub.2 OC(O)--, C.sub.6 H.sub.5 C(O)-- or C.sub.1 -C.sub.6 alkoxy-C(O)--; or wherein R and R.sup.1 together with the carbon atom to which they are attached comprise --C(O)--, and produces the desired 3-exomethylene compounds with low levels of the corresponding 3-methyl tautomers.