Patent GB-766605-A (GB)
Title: The method of preparing esters of n-carbamylamic acids
IPC: C08G63/685
Filed: 1954-10-29
Abstract: The invention comprises esters of a -olefinic N-carbamyl-amic acids obtained by reacting N-carbamylimides of the formula <FORM:0766605/IV(a)/1> (A=H or hydrocarbon residue) with a compound containing a non-tertiary alcoholic group, e.g. cellulose and ethers and esters thereof, polyglycols, polymeric alcohols formed by oxidizing and partially reducing iso-olefin/conjugated diolefin copolymers, alkyd resins having terminal alcoholic hydroxyl groups, polyvinyl alcohol and partial ethers and esters thereof, methylolphenol condensation polymers, and the polymeric alcohols obtained by reacting divinyl sulphone with glycols.  In the above formula the remaining bonds are attached to hydrogen or hydrocarbon radicals, there being one a -olefinic group and the carboxyl groups being in cis-configuration if capable of existing in stereoisomeric forms. Examples show the production of N-carbamyl-maleamic esters (A=H) of cellulose (cotton linters), ethyl cellulose (in solution), cellulose acetate (in solution), polyethylene and polypropylene glycols of various molecular weights, polymeric alcohols made from divinylsulphone and diethylene glycol, pentamethylene glycol or octane-1 : 2-diol, and the following alkyd resins: phthalic anhydride/ethylene glycol, phthalic anhydride/adipic acid/ethylene glycol, succinic acid/diethylene glycol, adipic acid/ethylene glycol/propylene glycol, tetrachlorophthalic acid/adipic acid/ethylene glycol/glycerol, sebacic acid/propylene glycol/glycerol, adipic acid/ethylene glycol/diethylene glycol, 3 : 6 - endomethylene - tetrahydrophthalic anhydride/diethylene glycol, and maleic anhydride/adipic acid/diethylene glycol.  The N-carbamyl - itaconamic and N - carbamylcitraconamic esters of the resin adipic acid/ethylene glycol/propylene glycol are also described.  The group A in the formula may also be methyl, ethyl, n-butyl, t-butyl, cyclohexyl, phenyl or benzyl.  The alkyd resin esters may contain one or two carbamyl-amine ester groups.  They are stated to be copolymerizable with conjugated alkadienes, as also are the esters of the divinylsulphone-glycol reaction products.  Plasticizers.-The ester obtained from N-carbamyl-maleamic acid and castor oil is stated to be a suitable plasticizer for ureaformaldehyde resins.ALSO:The invention comprises (1) the preparation of esters of a -olefinic N-carbamyl-amic acids by reacting N-carbamylimides of the formula <FORM:0766605/IV(b)/1> where A is hydrogen or a hydrocarbon residue (see Specification 740,591) with a compound containing a non-tertiary alcoholic group; and (2) the esters so obtained from aliphatic di- and poly-hydric alcohols and acids of not more than 7 carbon atoms. In the formula the remaining bonds are attached to hydrogen or hydrocarbon radicals, there being one a -olefinic group and the carboxyl groups being in cis-configuration if capable of existing in stereoisomeric forms.  The reaction is preferably carried out in a solvent which may be an excess of the alcohol; a catalyst such as zinc chloride may be used.  Examples show the production of esters of N-carbamyl-maleamic acid with methanol, ethanol, isopropanol, butanol, n-dodecanol, allyl alcohol, ethylene glycol (mono and bis esters), b -ethoxyethanol, b -chlorethanol, benzyl alcohol, castor oil, blown linseed oil, polyethylene glycols, polypropylene glycols and the long-chain polyhydric alcohols obtained by reacting divinyl sulphone with glycols such as diethylene glycol, pentane-1 : 5-diol and octane-1 : 2-diol. Further examples show the preparation of methyl N-carbamyl - itaconamate, methyl N - carbamylcitraconamate, benzyl N - (n - butylcarbamyl)-maleamate, benzyl N - (phenylcarbamyl)-maleamate and isopropyl N-(t-butylcarbamyl)-maleamate.  Many other suitable starting materials are mentioned in which the group A may also be methyl, ethyl, cyclohexyl or benzyl and the esterifying alcohol may be alkyl, aralkyl or cycloalkyl and may be substituted by halogen, nitro, alkoxy or carboxy groups.  Other alcohols are e.g. triethanolamine, b -morpholino-ethanol glycerol, pentaerythritol, glucose, sucrose, starch, sorbitol and partial ethers and esters thereof, glycerol and glycerides, N-methylolmaleimide and N : N1-dimethylolurea.