Caprolactam, methylation

Pyrimido[4,5-h]azepine-2,4-diones497 were prepared in 12-38% yield by reacting caprolactam methyl ether with aryl isocyanates at 150-155°C for 3-5 hr (73CB374). It was suggested that a ketene-0,A -acetal was first formed, which reacted with isocyanates via the 1,4-dipole form 495. In the final step, pyrimido[4,5-h]azepine-2,4-diones 497 were formed from perhydro-pyrimido[4,5-h]azepines 496 by the elimination of methanol. 

Ketones are an important class of industrial chemicals that have found widespread use as solvents and chemical intermediates. Acetone (qv) is the simplest and most important ketone and finds ubiquitous use as a solvent. Higher members of the aUphatic methyl ketone series (eg, methyl ethyl ketone, methyl isobutyl ketone, and methyl amyl ketone) are also industrially significant solvents. Cyclohexanone is the most important cycHc ketone and is primarily used in the manufacture of y-caprolactam for nylon-6 (see Cyclohexanoland cyclohexanone). Other ketones find appHcation in fields as diverse as fragrance formulation and metals extraction. Although the industrially important ketones are reviewed herein, the laboratory preparation of ketones is covered elsewhere (1). 

Additional areas for growth are expected to be ia copper leaching, caprolactam, pulp and paper, methyl methacrylate, and batteries (144). 

Hexanolactam, see Caprolactam 2-Hexanone, see Methyl n-butyl ketone 1 -Hexene... 

Caprolactam is a thermally unstable compound which on distillation may form methyl-, ethyl-, propyl-, and n-amylamines. Also, at high temperatures, CL reacts widi oxygen to form hydroperoxides which in the presence of iron or cobalt ions are converted into adipimide. /V-alkoxy compounds are also formed by the reaction of CL with aldehydes during storage. 

Natriumalanat7, Natrium-bis-[2-methoxy-athoxy]-dihydrido-aluminat8 und Dialkyl-aluminiumhydride reduzieren Lactame ahnlich wie Lithiumalanat zu cyclischen Aminen. Mit den beiden letzteren Hydriden kann auch in Benzol/Kohlen-wasserstoff gearbeitet werden. Eine Arbeitsvorschrift zur Herstellung von Azepan aus c-Caprolactam durch Reduktion mit Diathyl-aluminiumhydrid ist in ds. Handb., Bd. XIII/4, S. 220, mit Bis-[2-methyl-propyl]-aluminiumhydrid in der Lit. angegeben9. 

In analogy, Ugi et al. reported on a lactam formation by running a one-pot three components reaction the condensation of L-lysine 7, isobutyraldehyde and methyl isocyanide led to the corresponding a-amino-c-caprolactam 9, but the yield was not given. The authors presumed either a nucleophilic substitution of the ester 8 as the primary Ugi product by the amino function of the side chain or, alternatively, the nucleophilic attack of the NH2-group on an intermediately formed 0-acylamide and a subsequent rearrangement (Scheme 1) [4]. 

Imino ethers and, in particular, lactim ethers [141] such as O-ethylpyrrolidone 384a [142] or O-trimethylsilylcaprolactam 384b, which is formed, in equilibrium with N-trimethylsilylcaprolactam, on treatment of caprolactam with HMDS 2, condense readily with activated methylene compounds such as methyl or ethyl cyanoacetate to the y9-enamino esters 385 a and 385 b [140] whereas O-alkylureas such as 2-methoxyimidazoline 386 [143-146] afford products such as 387. 

Calcium carbide, 32, 70 Calcium carbonate, 32, 81 Calcium formate, 31,102 CAPROIC ACID, e-AMINO, 32, 13 e-Caprolactam, 31, 72 32, 15 e-CAPROLACTIM, O-METHYL-, 31, 72 CAPRONITRILE, a-ETHYL, 32, 6S Caproyl chloride, 31, 71 CARBANILINONITRILE, O-CHLORO, 31, 19... 

Methoxyphenylurea, 31,10,13 Methyl -acetylbenzoate, 32, 81 Methyl acrylate, 30, 65 32, 86 y-Methylallophanate, 32, 62 Methylamine, 30, 60 4 -Methyl-2-aminobenzophenone, 32,12 N-Methylaniline, 30, 62 31,110 N-Methylarylamines, preparation by reductive alkylation, 30, 59, 60 Methylation, of e-caprolactam, 31, 72 of quinacetophenone, with dimethyl sulfate, 31, 91 with methyl iodide, 31, 90 2-Methyl-3,l,4-benzoxaz-4-one, 32, 12 N-Methyl-a-bromo-n-butyranilide, 30, 63... 

Arex A process for removing aromatic hydrocarbons from petroleum streams by extraction with 1-methyl piperidone (N-methyl caprolactam) at 60°C. Developed by Leuna Werke, Germany. 

Lactams Lactams represent a special type of C=N system due to the tautomerization between the lactam (keto amine) and lactim (hydroxyimine) forms. The lactim form is much more favored for cyclic than for non-cyclic amides of carbocyclic acids. In the reaction of complex 2b with N-methyl-e-caprolactam, a simple ligand exchange reaction occurs and complex 87 can be isolated. With P-propiolactam, the alkenyl-amido complex 88 is formed, which indicates an agostic interaction. The reaction of complex 1 with e-caprolactam gives, after elimination of the alkyne and of molecular hydrogen, complex 89 with a deproto-nated lactam in a r]2-amidate bonding fashion [47]. 

Epsilon-caprolactam from epsilon-caprolactam, 4-ethyl-2-pyrrolidinone, 5-methyl-2-piperdinone, 3-ethyl-2-pyrrolidinone, 3-methyl-2-piperdinone Silicalite-1 Methanol, acetonitrile [197,198[... 

With thermoplastics casting is, in general, not possible because of the high melt viscosity, except when polymerisation has still to take place the monomer or prepolymer is polymerised in the mould. This is, e.g. possible with PMMA and PA-6 (from methyl-methacrylate and caprolactam, respectively). 

Problem 16.56 Indicate the reactions involved and show the structures of the following condensation polymers obtained from the indicated reactants (a) Nylon 66 from adipic acid and hexamethylene diamine (b) Nylon 6 from e-caprolactam (c) Dacron from methyl terephthalate and ethylene glycol (d) Glyptal from glycerol and terephthalic acid (e) polyurethane from diisocyanates and ethylene glycol. ... 

N-Amyl Methyl Ketone Caprolactam, Liquid Oils Edible, Lard Tetraethyl Pyrophosphate Arsenic Trisulfide Copper Acetoarsenite Arsenic Trisulfide Benzene Hexachloride Lactic Acid Ammonium Lactate Ethyl Lactate... 

More extensive studies with 1 have been reported by Rogic and co-workers in connection with new synthetic approaches to caprolactam. They established that I can cleave o-quinones, catechols, and phenols under anaerobic conditions. Thus catechol, o-benzoquinone, and phenol are oxidized by 1 to m,m-muconic acid methyl ester. The paper presents several lines of evidence that oxygen docs nol... 

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