2-Pyrrolidinone , conversion

Lactam polymerizations (nonassisted as well as assisted) are usually complicated by heterogeneity, usually when polymerization is carried out below the melting point of the polymer [Fries et al., 1987 Karger-Kocsis and Kiss, 1979 Malkin et al., 1982 Roda et al., 1979]. (This is probably the main reason why there are so few reliable kinetic studies of lactam polymerizations.) An initially homogeneous reaction system quickly becomes heterogeneous at low conversion, for example, 10-20% conversion (attained at a reaction time of no more than 1 min) for 2-pyrrolidinone polymerization initiated by potassium t-butoxide and A-benzoyl-2-pyrrolidinone. The (partially) crystalline polymer starts precipitating from solution (which may be molten monomer), and subsequent polymerization occurs at a lower rate as a result of decreased mobility of /V-acyl lactam propagating species. 

Flydroformylation A catalyst solution consisting of dicarbonylacetylacetonato rhodium (I) (0.063 g) and dicyclohexyl-(3-sulfonoylphenyl)phosphine mono sodium salt (1.10 g) in n-methyl pyrrolidinone (NMP) (16.0 g) was placed in a 100 mL stainless steel autoclave at 75 C under 200 psig synthesis gas. After 15 minutes soy methyl esters (34.05 g) were added and the synthesis gas pressure raised and maintained at 400 psig for 3 hrs resulting in the desired conversion of unsaturation. 

Commercially available VP is usually over 99% pure but does contain several methyl-substituted homologues and 2-pyrrolidinone. The vinylation of 2-pyrrolidinonc is carried out under alkaline catalysis analogous to the vinylation of alcohols. 2-Pyrrolidinone is treated with ca 5% potassium hydroxide, then water and some pyrrolidinone are distilled at reduced pressure. A ca 1 1 mixture (by vol) of acetylene and nitrogen is heated at 150- L60°C and ca 2 MPa (22 atm). Fresh 2-pyrrulidiuone and catalyst are added continuously while product is withdrawn. Conversion is limited to ca 60% to avoid excessive formation of hy-products. The AI-vinyl-2-pynolidinone is distilled at 70-85°C at 670 Pa (5 mm Hg) and the yield is 70-80%. 

A charged support, double layered hydroxide, that can be described by the general formula, Mgi xAlx(OH)2Cl zH20, was used to immobilise [PdCl4]2-/811 While results with this catalyst were only poor in A-methyl pyrrolidinone, good conversion and selectivity was obtained in [(C4)4N]Br with arylchlorides as substrates. By employing microwave irradiation coupling between chlorobenzene and styrene afforded the desired product in 95% yield within 30 minutes. The products were isolated by distillation and the catalytic activity remained essentially stable for at least 5 runs. 

Oxazabicyclohexanes 134 have been postulated as undetected intermediates in the photolytic conversion of 2-acyl-1-pyrroline 1-oxides into pyrrolidinones and acyl pyrrolines. 

Carbonyl reduction. Conversion of carboxylic acids to aldehydes can be achieved by DIBALH reduction of the derived trimethylsilyl esters. The cyclic carbonyl group of N-Boc pyrrolidinones is reduced and further treatment of the products with quinolinium camphorsulfonate delivers the enecarbamates. ... 

The first example of the AHR was reported in 1989, and involved the conversion of the pro chiral vinyl iodides 12a-c into the chiral decalin systems 13a-c, as shown in Scheme 3 [24]. The reaction conditions (dipolar aprotic solvent and presence of silver salts), while similar to those of a previously reported non-enantioselec-tive method [16], differ crucially in respect of the choice of chiral ligand and of solvent - very low or negligible ee s were obtained using THE, MeCN, or DMSO, with the preferred solvent being N-methyl-2-pyrrolidinone (NMP). Similarly, the widely used chiral phosphine ligands BPPM [ 1 -tert-butoxycarbonyl-4-diphe-... 

Two different approaches to ( —)-statine (831), an unusual amino acid component of pepstatine, both employ 793c as their starting point. In the first synthesis (Scheme 120) [183], reduction of 793c with sodium borohydride produces a mixture of two isomeric 5-hydroxy-pyrrolidinones, from which the pure cis product 824 crystallizes in 85% yield. Conversion of bisacetate 825 to thioether 826 followed by removal of the acetate and silylation of the resulting alcohol affords 827. Radical cyclization of 827 produces a 3 2 mixture of isomers 828. Desilylation and debenzylation gives 829 as a single diastereomer. The Boc-protected intermediate 830 intersects with a known synthesis of ( —)-statine (831). 

Succinic acid is a chemical which has found applications in many areas the most important ones being food additives, soldering fluxes, and pharmaceutical products (1). The conversion of succinic acid to industrially important chemicals such as 1,4-butanediol (EDO), tetrahydrofuran (THF), y butyrolactone (GEL), N-methyl pyrrolidinone (NMP), and 2-pyrrolidinone (2P) recently has been made possible by the development of a number of catalytic processes (2,3). This new development is expected to considerably expand the market for succinic acid. 

Several transformations involving CO insertion into a Pd-heteroatom bond have been developed that lead to incorporation of two molecules of CO into the heterocyclic product. This approach to heterocycle synthesis is exemplified by a synthesis of dihydroindolones reported by Gabriele [101]. As shown below, treatment of ortho-alkynyl aniline 157 with a Pd catalyst under CO in methanol afforded 158 in 50% yield (Eq. (1.62)). A similar strategy has been employed for the conversion of alkene 159 to pyrrolidinone 160 (Eq. (1.63)) [102]. 

Silverman prepared 5S-hydroxymethyl-2-pyrrolidinone 5.42) by essentially the same route as shown above. Conversion of the hydroxymethyl group to a mesylate was followed by its reduction to a methyl group with zinc and sodium iodide, giving 5R-methyl-2-pyrrolidinone (5.44).26 The 5S-methyl derivative was prepared in an identical manner from D-glutamic acid. When 5.44 was heated with 6N HCl,... 

Cellulose can be converted into a hemiacetal derivative, methylol cellulose , by reacting with formaldehyde in methyl sulphoxide. Other aprotic solvents, such as pyridine, AA-dimethylformamide, AA-dimethylacetamide, A-methyl-2-pyrrolidinone, and thiolane-1-oxide can be substituted for methylsulphoxide for this conversion. More concentrated solutions of methylol cellulose could be obtained when cellulose and paraformaldehyde were heated together in the solvent than when formaldehyde gas was bubbled through a suspension of cellulose in the solvent. Solutions of 10% cellulose in methylsulphoxide could be obtained by this method. During the swelling of cellulose in ethanolamine, ethylenediamine, and methyl sulphoxide, the solvent retention capacity of cellulose at 20—120°C decreased by 10—20%, depending on the solvent."... 

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