N-Methyl-2-pyrrolidone as solvent

Special solvent. Newman - recommends N-methyl-2-pyrrolidone as solvent for the reaction of an aryl halide with cuprous cyanide to produce the corresponding nitrile. Dimethylformamide (b.p. 153°) has been suggested as a better solvent than originally used pyridine (b.p. 115°), but l-methyl-2-pyrrolidone has an even higher boiling point and seems still more satisfactory. An example is the synthesis of... 

Parrish (1977) reviewed the research and development of lactose ester-type surfactants carried out by Scholnick and his colleagues (Scholnick et al. 1974, 1975 Scholnick and Linfield 1977). Their initial attempts to form lactose esters followed the same transesterification procedures that had been used with sucrose (a fatty acid methyl ester in N,N-dimethylformamide with potassium carbonate as the catalyst). Their successful approach was the reaction of lactose in N-methyl-2-pyrrolidone as the solvent with fatty acid chlorides, resulting in yields of 88 to 95% for esters of lauric, myristic, palmitic, stearic, oleic, and tallow fatty acids. The principal product was the monoester, which is important for detergent use, since diesters and higher esters of lactose are not water soluble. 

N-methyl-2-pyrrolidone, a solvent used as an alternate to furfural and phenol for the extraction of lubricating oil fi-actions. 

The electrodes for examination were produced by smearing of suspension of active materials in the solution of binding substance -po 1 yviny 1 idcncfluoride (PVDF) - on the metal substrate by means of applicator "Doctor Blade" by Hohsen Corp. N-methyl-2-pyrrolidone was used as the solvent for the binding substance. 

Alkyl halides can be hydrolyzed to alcohols. Hydroxide ion is usually required, except that especially active substrates such as allylic or benzylic types can be hydrolyzed by water. Ordinary halides can also be hydrolyzed by water,442 if the solvent is HMPA or N-methyl-2-pyrrolidone.443 In contrast to most nucleophilic substitutions at saturated carbons, this reaction can be performed on tertiary substrates without significant interference from elimination side reactions. The reaction is not frequently used for synthetic purposes, because alkyl halides are usually obtained from alcohols. 

In general, electrocarboxylation reactions are carried out in aprotic solvents such as acetonitrile (ACN), N,N-dimethylformamide (DMF) or N-methyl-2-pyrrolidone (NMP) in a one-compartment cell by the use of sacrificial anodes (Al or Mg), as the use of these systems generally provide important advantages [7, 10-12] that include ... 

Starting materials and solvents were purchased from Aldrich Chemical Co. acetonitrile (ACN), N,N-dimethylformamide (DMF), and N-methyl-2-pyrrolidone (NMP) were obtained anhydrous in Sure/Seal bottles and used as received. The polyamic acid of PMDA-ODA (2545 Pyralin) was supplied by DuPont. The soluble polyimide XU-218, derived from 3,3, 4,4 -benzophenone tetracarboxylic dianhydride (BTDA) and diamino-1,1,3-trimethyl-3-phenylindan isomers (DAPI) was purchased from Ciba-Geigy Corp. The acetylene terminated imide oligomer powder (Thermid MC-600) derived from BTDA, aminophenylacetylene, and 1,3-bis (2-aminophenoxy) benzene (APB) was obtained from National Starch and Chemical Company. Kapton Type II (PMDA-ODA) films were obtained from DuPont Co., Apical polyimide films were obtained from Allied Corp., and Upilex Type-S and Type-R polyimide films derived from 3,3, 4,4 -biphenyl tetracarboxylic dianhydride (BPDA) plus p-phenylenediamine (PDA) and ODA, respectively were obtained from ICI Americas Inc. 

In method (a), an alkyl halide (or tosylate) reacts with [Fe(CO>4] " in N-methyl-2-pyrrolidone to give an anionic iron alkyl (I), some of which have been isolated and characterized. Further reaction with another alkyl halide gives a complex tentatively formulated as (2), which may decompo.se to the ketone via the complex (3) formed by solvent-assisted migratory insertion. No alkyl coupling products are detected. 

By this method, 1-bromonaphthalene affords 1-naphthonitrile in 94% yield after refluxing for 4 hrs. with pyridine as solvent the reaction mixture is heated in an oil bath at 215-225° for 15 hrs., and the yield is 82-90%. Efficient procedures for liberating the nitrile from the cuprous halide complex involve pouring the brown reaction mixture into an aqueous solution of ferric chloride (oxidizes Cu+ to Cu ", which forms no complex), ethylenediamine (forms complexes with Cu+ and Cu " ), or sodium cyanide (forms soluble sodium cuprocyanide). The higher-boiling N-methyl-2-pyrrolidone (b.p, 202°) is also satisfactory, but is more expensive. 

Since PPS is prepared by reaction of p-dichlorobenzene (I) and Na2S in N-methyl-2-pyrrolidone (NMP) at ca, 240° (13), the reaction of p-dlhalobenzenes with Na Se and Na2Te appeared to be at attractive approach. We note that an unsuccessful attempt to synthesize PPSe from p-dibromobenzene (2) and Na2Se has been reported. (14) As we have recently found (la-b) that alkali metals react directly with selenium and tellurium in 1 1 and 2 1 atomic ratios in dipolar aprotic solvents, thus avoiding the use of liquid NH3 commonly used for the preparation of these reagents, and that these reagents react readily with aromatic halides, which are not activated in the usual sense for a nucleophilic... 

Reduction of ArCHO. N-Methyl-2-pyrrolidone is used as solvent. When an ArCN is treated similarly, a pyrrolo[2,3-d]pyrimidine is formed. 

Nucleophilic Opening. A neutral hydrolysis medium, more effective than water alone is provided by the combination of water and a polar aprotic solvent eg. HMPA or NMP (N-methyl-2-pyrrolidone). Thus 15 aqueous NMP at 130°C containing NaHCO will open terminal (but not internal) epoxides to diols (>90 ) as well as convert haloalkanes to alcohols in high yields. 

N-methyl-2-pyrrolidone For experimental purpose and as an intermediary solvent only. 

Isolute ENV+ was also used in the determination of A/ methyl-2-pyrrolidone and its metabolites in human plasma and urine [277]. At present, N-methyl-2-pyrrolidone replaces hexane and dichloroethane in many chemical processes because it is thought to be less harmful to human health. However, animal studies revealed harmful and reproductive toxic effects. Because of this, the monitoring of individuals exposed to the solvent is not unreasonable. After entering the human body, N-methyl-2-pyrroli-done quickly metabolizes as... 

In the bulk phase-separation approach, an organic solution of a polymer dissolved in a water-miscible solvent is injected into the tissue defect. After injection, the solvent diffuses away from the injection site, resulting in precipitation of the water-insoluble polymer. Selection of an appropriate solvent, which must be non-cytotoxic and not harmful to host tissue, is a key factor for success of the bulk phase-separation system. Two solvents that meet these criteria are N-methyl-2-pyrrolidone (NMP) and dimethyl sulfoxide (DMSO). In recent years, improved strategies for removal of the solvent and release of growth factors have been active areas of investigation. However, the requirement of a solvent to induce phase separation of the polymer limits the scale at which this approach can be applied in vivo. Even for relatively biocompatible solvents such as NMP and DMSO, injection of large volumes is anticipated to adversely affect host tissue, as well as the ability to eliminate the solvent from the body. 

The recovery of pure aromatics from hydrocarbon mixtures is not possible using distillation process because the boiling points of many non-aromatics are very close to benzene, toluene, etc. Also, azeotropes are formed between aromatics and aliphatics. Three principle methods are used for separation azeotropic distillation, liquid-liquid extraction, and extractive distillation. Three major commercial processes have been developed for separation Udex, Sulpholane, and Arosolvan. Over 90% plants now use one of these processes. Each use an addition of solvent such as a mixture of glycols, tetramethylene sulfone, or N-methyl-2-pyrrolidone to aid in the extraction of aromatics. This occurs with high precision and efficiency. Pure benzene, toluene, and xylene are produced by these processes. 

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