Bis methylation

Bi Methylation of 8-Hydroxypsoralen 115 mg of 8-hydroxypsoralen was dissolved in 10 ml absolute methanol, an excess of diazomethane dissolved in ether was added and the mixture allowed to stand at room temperature with occasional stirring for 3 hours. The next day the reaction mixture was reduced in volume to 3 ml by evaporation on the steam bath and the concentrate was held in a refrigerator overnight. The next day, fine needles (80 mg) of 8-methoxypsoralen were filtered from the solution. The compound had a MP of 145° to 146°C and was obtained in a yield of 65% of theory. 

Mizutani and coworkers57a confirmed the presence of polychloro(methylsulfonyl)biphenyls (159-170) as sulfur-containing metabolites of chlorobiphenyls (Cl-BP) in the feces of mice based on both GLC-mass spectrometry and chemical derivatization. In some cases comparison with authentic samples (161 and 162) was also made. When preparing 161 and 162,2,5-dichloro-3-(methylsulfonyl)aniline, 2,5-dichloro-l-iodo-3-(methylsulfonyl)benzene and 2,2, 5,5 -tetrachloro-3,3 -bis(methyl-sulfonyl)biphenyl were also obtained and their four peak El mass spectra reported572. Similar data were given for the corresponding 4-substituted intermediates, which were involved in the preparation of 162. Also 2,4, 5-trichloro-2 -(methylsulfonyl)-biphenyl was prepared and its four peak mass spectra given. Metabolites 163 and 164 were also identified by comparison with the authentic standards. 

Bidentate sulphoxides, such as 1,3-bis(methylsulphinyl)propane, 1,4-bis(methyl-sulphinyl)butane and 1,2-bis(ethylsulphinyl)ethane, have been synthesized and employed as ligands toward Mn2 +, Co2 +, Ni2 +, Cu2 + and Zn2 + 204. All metal ions are bound to the ligands via the oxygen of the sulphoxide groups and are six-coordinate, as shown in Scheme 20, with the exception of Cu2+, which is four-coordinate. 

Methyl 2-0-(methyl 2-deoxy-a-D-glucopyranosid-2-yl)-a-D-glucopyranoside or bis(methyl 2-deoxy-a-D-glucopyranosid-2 yl) ether... 

Benzo[c]furans (isobenzofurans) are very reactive but generally unstable dienes which are prepared in situ and trapped. The in ihu-generated isobenzo-furan 33 was trapped by cycloaddition reaction with bis(methyl (S)-lactyl) ester 34 to afford [32] optically active naphthols (Equation 2.12). The cycloaddition was carried out in the presence of a catalytic amount of glacial acetic acid and represents a facile one-pot procedure to synthesize substituted naphthols. 

Crowded imidazolides do not react with magnesium bis (methyl malonate) because of steric hindrance. 551... 

The preparation of ZnSe materials is an area of interest and study. The coordinating ability of the solvent used in the solvothermal synthesis of zinc selenide was demonstrated to play an important role in the nucleation and growth of nanocrystalline ZnSe.604 Thermolysis of bis [methyl( -hexyl)di-seleno]carbamato]zinc gave highly monodispersed particles characterized by electronic spectroscopy, photoluminescence, X-ray diffraction, and electron microscopy.605... 

A route for the asymmetric synthesis of benzo[3]quinolizidine derivative 273 was planned, having as the key step a Dieckman cyclization of a tetrahydroisoquinoline bis-methyl ester derivative 272, prepared from (.S )-phcnylalaninc in a multistep sequence. This cyclization was achieved by treatment of 272 with lithium diisopropylamide (LDA) as a base, and was followed by hydrolysis and decarboxylation to 273 (Scheme 58). Racemization could not be completely suppressed, even though many different reaction conditions were explored <1999JPI3623>. 

Miktoarm stars of the A(BC)2 type, where A is PS, B is poly(f-bulyl acrylate) (PtBA), and C is PMMA [161] have been synthesized, by using the trifunctional initiator 2-phenyl-2-[(2,2,6,6-tetramethyl)-l-piperidinyloxy] ethyl 2,2-bis[methyl(2-bromopropionato)] propionate (NMP, ATRP) (Scheme 86). In the first step, a PS macroinitiator with dual < -bromo functionality was obtained by NMP of styrene in bulk at 125 °C. This precursor was subsequently used as the macroinitiator for the ATRP of ferf-bulyl acry-... 

Figure 25 Structure of bis[methyl(w-hexyl)dithio-/selenocarbamato]-zinc and -cadmium complexes,...

Bis [Methyl-2-(3-d imethy lea rbamoxypyridyl)methy lam ino] nonane Dimethobromide... 

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