A-Methyl-2-pyrrolidone

Leira HL, Tilmes A Svendsen K, et al Irritant cutaneous reactions to A/-methyl-2-pyrrolidone (NAIP). Contact Derm 27 148-150, 1992... 

Akesson B, Paulsson K Experimental exposure of male volunteers to A/-methyl-2-pyrrolidone (NMP) Acute effects and pharmacokinetics of NMP in plasma and urine. Occup Environ Med 54(4) 2 36-240,1997... 

The cyclizations of /3-hydroxycarboxamides with aldehydes, ketones, or their equivalents results in l,3-oxazin-4-one derivatives <1996CPB734, 2006BMC584, 2006BMC1978>. In the acid-catalyzed condensation of salicylamide 422 with (—)-menthone, a 2 1 mixture of C-2-epimeric 27/-l,3-benzoxazin-4(37r)-ones 202 and 423 was formed, the equilibrium of which could be shifted toward the (23 )-enantiomer 202 by base-catalyzed isomerization with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in A -methyl-2-pyrrolidone (NMP) to yield a 14 1 mixture of 202 and 423 (Equation 44) <1996TL3129>. 

Two methods have been described for the catalytic A -arylation of tetrahydro-l,2-thiazine 1,1-dioxides (Equation 22 Table 1) <2004TL3305>. The first involves the copper-catalyzed N-arylation of sulfonamide 151 in the presence of 2,2 -bipyridine and K3PO4 in A -methyl-2-pyrrolidone (NMP) at 120°C. A variety of aryl bromides/iodides and... 

To a stirred flask containing a suspension of 4.8 gm (0.2 mole) of sodium hydride in 50 ml of THF under a nitrogen atmosphere is added dropwise 13.3 gm (0.2 mole) of cyclopentadiene. In a separate flask are mixed 19.8 gm (0.2 mole) of A-methyl-2-pyrrolidone and 25.2 gm (0.2 mole) of dimethyl sulfate. (NOTE Separately A-methyl-2-pyrrolidone and dimethyl sulfate should be anhydrous and should be purified by distillation before reacting with each other to form the complex.) The latter mixture is heated for 20 min on a steam bath, cooled, and then added dropwise to the cyclopentadienylsodium solution at —5°C. After the addition, the reaction mixture is stirred for 2 hr, filtered, the filtrate concentrated, and the residue is obtained as a brown oil. On cooling, the brown oil solidifies and is recrystallized from cyclohexane to afford pale-yellow needles weighing 14.0 gm (50%), m.p. 100°-101°C. 

Systematic work has been carried out on the replacement of chlorines in tetra- and pen-tachloropyridines with fluorine.117,118 Potassium fluoride has been used as the reagent with (tetramethylene sulfone, A-methyl-2-pyrrolidone) and without (autoclave) solvent. Besides per-fluoropyridine, a mixture of chlorofluoropyridines has been obtained. 

PolyQ>phenylene sulfide) (PPS) deserves much attention as an engineering and a conductive plastic and in some cases as a specialty polymer with excellent performance. Lenz first reported that PPS is synthesized by the polycondensation of / -halothiophenolate alkali-metal salts at high temperature [83], Commercially PPS is produced by the polycondensation of -dichlorobenzene and sodium sulfide in A-methyl-2-pyrrolidone [84]. These polymerizations proceed only at high temperature and pressure, and it is difficult to remove the metal halides such as sodium chloride as by-products in order to obtain pure PPS salt contamination degrades the electric performance and moldability. 

An unusual synthesis of a pyrrolo[2,3- ]pyrimidine without a functional group is based on the reaction of benzonitrile with A-methyl-2-pyrrolidone. These two compounds, when heated in the presence of sodium telluride, give low yields of 2,4-diphenyl-7-methylpyrrolo[2,3- ]pyrimidine <93JOC24l>. The yields could not be improved, thereby limiting the usefulness of the method. 

Solubility has not been analytically explored. Solubility has been explored for purification, separation, or complexa-tion. In general, good solvents for CE cryptands are polar organic solvents such as acetone, chloroform, methylene chloride, MeCN, dimethylformamide (DMF), A -methyl-2-pyrrolidone (NMP), ethyl acetate, and alcohols. Table 6 summarizes the column chromatographic conditions used for cryptand purification. 

Fluoropyrazine has been prepared from 2-chloropyrazine and anhydrous potassium fluoride in refluxing dimethyl sulfoxide (882) or Af-methyl-2-pyrrolidone at 185° (883). Similarly 3-fluoro-2,5-dimethylpyrazine has been prepared from its chloro analogue and dry potassium fluoride in A -methyl-2-pyrrolidone and 2-chloro-6-fluoropyrazine and 2,6-difluoropyrazine from 2,6-dichloropyrazine (883). 

The discovery of the above-mentioned class of highly efficient alkyne carbonylation catalysts originated from a general study of reactions homogeneously catalyzed by cationic metal complexes [6, 8, 9], e. g., the methoxycarbonylation of propyne (eq. (2)). The catalysts applied were cationic palladium phosphine systems prepared in situ from three components (1) palladium acetate, (2) an excess (10-40-fold on Pd) of a (mono)phosphine ligand(L) and (3) an acid (HX) [8]. Methanol was used as both reactant and solvent, but many other solvents can also be used, such as A-methyl-2-pyrrolidone (NMP) or product MMA. 

Tetracycline A/-methyl 2-pyrrolidone CO2 15 313 Orifice diameter, 60 Spheres Reverchon (1 01 ... 

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