2-mcthyl- -iodide

The corresponding reaction with 2-methylamino-5-nitroaniline affords an unambiguous synthesis of l-methyl-6-nitroquinoxaIin-2-one, the A -mcthyl derivative of (6) this product is also obtained by treatment of (6) with methyl iodide and methanolic sodium methoxided ... 

Methyl hydrogen sebecate, 41, 34 Kolbe electrolysis of, 41, 33 1-Methylindole,40, 68 Methyl iodide, methylation of dihydroresorcinol with, 41, 57 Methyl isocyanide, 41, 15 Methyl 4-mcthyl-4-nitrovalerate, hydrolysis to acid, 41, 24 N-Methyl-N-nitrosoterephthalamide, preparation of diazomethane from, 41, 16... 

The key intermediate for the antibacterial agent levofloxcin, (,S>( )-7,8-difluoro-2,3-dihydro-3-methyl-4H-l,4-benzoxazin, was prepared by the asymmetric hydrogenation of (442) by the catalyst system made in situ from [Ir(cod)Cl]2, biphosphine and bismuth(III) iodide.703 The product was isolated in 96% yield, with an enantiomeric purity of 90% for the biphosphine (2S,45)-BPPM,(2S,45)-N-( -butoxy-carbonyl)-4-(diphcnylphosphino)-2-[(diphcnylphosphino)mcthyl]-pyrrolidine. 

Methylfluorene has been prepared by cleavage of ethyl 9-methyl-9-fluorenylglyoxylate,4 by the decarboxylation of 9-methylfluorene-9-carboxylic acid,4 by the decarboxylation of 9-fluorenylacetic acid,6 by the cleavage of 9-methyl-9-acetyl-fluorene with alcoholic potassium hydroxide or soda-lime,6 by the reduction of 9-methyl-9-fluorenol with hydriodic acid in acetic acid,7 by the reaction of 9-fluorenyllithium 8 or -sodium 9 with methyl iodide or methyl sulfate,9 by the cyclization of diphenylmethyl carbinol over platinum-on-carbon at 300°,10 by the reaction of ethyl 9-methoxymcthyl-9-fluorcnylcarboxylate,11 by the diazotization and heating of 2-ethyl-2-aminobiphenyl,12 by the dehydration and then reduction of 9-mcthyl-9-fluorcnol,13... 

CN iV,/V-diethyl-iV-mcthyl-2-[[4-[4-(plienylthio)phcnylJ-37/-l, 5-bcnzodiazepin-2-yl]thio]cthanaminium iodide... 

Thus the hypothesis in Figure 3.4 is indeed effective for designing asymmetric synthesis. However, the main drawbacks in the transformation of 32 into 33 are low chemical yield and difficulty in removing the (V-mcthyl protective group. Further investigation of other (readily removable) nitrogen substituents and conditions for asymmetric induction are shown in Table 3.4. The best result was obtained with A-methoxymethyl(MOM)-A-Boc derivative 40. Treatment of 40 with KHMDS in toluene-THF (4 1) at —78°C for 30 minutes followed by the addition of methyl iodide afforded 41 in 96% yield and 81% ee (entry 9).27,28 Use of a toluene-THF (4 1) mixture as a solvent is crucial for both high yield and enantioselectivity (entries 7-9). 

Mcthylenedioxyplienylarsinio aoid and salts, 522. lO-Mcthyl-lO-ethyl-5 10-dihydroiihcnarsazonium iodide, 452. 

The products produced by interaction of diazonium salts and iodides are unstable and liable to be explosive in the solid state. They are usually the triiodides, but monoiodides have been isolated under specific conditions from diazotised aniline and o-toluidine. Products prepared from diazotised o-. m- or p-nitroanilines, m-chloro-, -methoxy-, or -mcthyl-anilme are too imstable to isolate, decomposing below 0°C. 

Acctamino-3-methyl-2-methylthio- -iodid 194 5-Acetamino-3-mcthyl-2-phenyl- -chlorid 125 5-Acetamino-2-methylthio- 329 4-Acetamino-2-mcthylthio-3-phenyl- -iodid 194... 

Mcthyl-3-(2-oxo-propyl)- -chlorid 350 3-Methyl-2-phenyl- -iodid 349 3-Methyl-4-phenyl- -perchlorat 193 3-Methyl-5-sulfonato- 226... 

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