| 摘要 |
The dehydrated acid form of a sulphonic acid cation exchange resin having a macroreticular structure is used to catalyse organic reactions in non-aqueous media. The examples are sulphonated copolymers of styrene and divinylbenzene. The catalysts are particularly useful for the preparation of esters from olefins and carboxylic acids. In examples (1), (2) tert. butyl methacrylate is prepared from methacrylic acid and isobutylene (4). tert. butyl acetate from acetic acid and isobutylene. (5). tert. butyl undecylenate from undecyleric acid and isobutylene (6). tert. butyl oxalate from oxalic acid and isobutylene (7) tert. butyl malonate from malonic acid and isobutylene (8). tert. butyl benzoate from benzoic acid and isobutylene. (9) 1, 1-dimethyl pentyl chloroacetate from chloracetic acid and 2-methyl-1-hexene. (10). tert. butyl formate from formic acid and isobutylene. The examples mention other olefins which may be used to give tert. esters. Suitable olefins and acids are also listed. The preparation of ethyl methacrylate from methacrylic acid and ethylene is also described, and the similar preparations of isopropyl acrylate, acetate and 2-ethyl hexoate as well as of sec. octyl acetate, sec. dodecylacetate, sec. octadecyl acrylate, sec. tricosyl acrylate, cyclopentyl acetate and cyclohexyl propionate are referred to. The catalysts are also useful in the following reactions:- Preparation of lactones, exemplified by the preparation of g -valerolactone from methyl-4-pentenoate and acetic acid, and from 4-pentenoic acid. Alkylation of aromatics, exemplified by the preparation of isopropyl toluenes from toluene and propylene, and by the alkylation of toluene with tetrapropylene. Alkylation of phenols, exemplified by the preparation of p-tert.-octyl phenol from phenol and diisobutylene, and of nonyl phenols from phenol and nonene. Ketone and aldehyde condensation exemplified by the preparation of 7-methylpentadec-7-en-9-one from methyl hexyl ketone; of 2-cyclohexenyl-cyclohexanone from cyclohexanone, and of 2-ethylhex-2-enal from n-butyraldehyde. Acylation of olefins, exemplified by the preparation of 3, 5, 5-trimethylhept-3-en-2-one from diisobutylene and acetic anhydride. Acylation of aromatics, exemplified by the preparation of p-methoxyacetophenone from anisole and acetic anhydride, of dimethylacetophenone from xylene and acetic anhydride, and of phenyl acetate and hydroxyacetophenones from phenol and acetic anhydride. Decomposition of cumene hydroperoxide to phenol and acetone. The Von Pechmann reaction, exemplified by the preparation of 4-methyl-7-hydroxycoumarin by reaction of resorcinol with ethyl acetoacetate in presence of iso-octane.ALSO:A sulphonic acid cation exchange resin having a macroreticular structure and prepared from a polymer of a mixture of monoethylenically unsaturated monomer and polyethylenically unsaturated cross-linking agent (see Specifications 932,125 and 932,126) is dehydrated e.g. by heating under reduced pressure, to form an acid catalyst for use in reactions brought about in non aqueous media. Dehydration may also be effected by azeotropic distillation e.g. with a hydrocarbon until no more water is removed, or by means of acid anhydrides. In examples catalysts are prepared from mixtures of styrene and divinyl benzene, containing from 6-55% of divinyl benzene. The mixtures are polymerised in presence of a liquid which dissolves the monomers but has little or no solvating action on the polymers. Suitable liquid precipitants are tert. amyl alcohol, iso-octane and sec.-butyl alcohol. The polymer particles are sulphonated, and the sulphonated product washed with di-ionised water and dehydrated at 105-125 DEG C. and 5-10 min. pressure.ALSO:The dehydrated acid form of a sulphonic acid cation exchange resin having a macroreticular structure is used to catalyse the polymerization of olefins to form low molecular weight polymers. In the examples, the catalysts on sulphonated copolymers of styrene and divinylbenzene. In one example, isobutylene is polymerized to a mixture of dimer, trimer and tetramer. The rate of polymerization may be increased by addition of a little acetic acid or of tert.-butyl acetate. In another example, a mixture of nonenes is heated at 130 DEG C. for 8 hours with a catalyst according to the invention. The product cut boiled between 145 DEG and 176 DEG . at 20 mms. Specifications 932,125 and 932,126 are referred to. |
