VOLUME 2 -methoxy

Butyl glycol ethers, the largest volume derivatives of -butyl alcohol used ia solvent appHcations (10), are obtained from the reaction of 1-butanol with ethylene oxide. The most important of these derivatives, 2-butoxyethanol, is used principally ia vinyl and acryHc paints as well as ia lacquers and varnishes. It is also employed ia aqueous cleaners to solubilize organic surfactants. 2-Butoxyethanol [111-76-2] has achieved some growth at the expense of the lower alkoxyethanols (ie, methoxy and ethoxyethanol) because of 2-butoxyethanol s lower toxicity. 

C. 7 ricar6oni/Z[( 1,2,3,4,5-jj)-l-and 2-methoxy-2,4 -cydohexadien-l-yl]-irTriphenylmethyl tetrafluoroborate [Methylium, triphenyl-, tetrafluoroborate] (34 g., 0.103 mole) (Note 20) is dissolved in a minimum volume of dichloromethane and 18 g. (0.072 mole) of tricarbonyl (1- and 2-methoxy-l,3-cyclohexadiene)iron dissolved in a like volume of dichloromethane is added. The resulting dark solution is left for 20-30 minutes and then added with stirring to three times its volume of ether (Note 21). The precipitate is collected and washed with ether to 5ueld 21-22 g. (87-91%) of product as yellow solid (Note 19). 

A solution of 5 grams of 6,7-dimethoxy-3-methyl-1-(4 -ethoxy-3 -methoxybenzyl)-lsoquin-oline in 100 cc of ethanol is treated with a solution of 1.5 grams of phosphoric acid in 10 cc of ethanol. 10 cc of water are added to effect complete solution, and the reaction mixture is then cooled and ether is added until precipitation of the salt is complete. The precipitate of 6,7-dimethoxy-3-methyl-T(3 -methoxy-4 -ethoxybenzyl)-isoquinoline phosphate is filtered off and recrystallized from 85% ethanol by the addition of 2 volumes of ether. 

By using the same molecular proportions the following m-nitrophenols were prepared in equally good yields from the corresponding m-nitroanilincs 3-methoxy-5-nitrophenol and 3-nitro-4,6-xylenol. In the former case it is advisable to use slightly more ice in the diazotization and add the diazonium solution to a mixture of equal volumes of sulfuric acid and water. 

Polystyrene was prepared by the anionic polymerisation of styrene in toluene plus THF mixtures (4 1 volume ratio) using n-butyl lithium as initiator. After removing a sample for analysis at this stage, the remainder of the living polystyrene was reacted with a five molar excess of trichloromethylsilane for 15 min and then excess methanol introduced. The methoxy-terminated polystyrene was freeze-dried from dioxan. The method described here essentially follows the route proposed by Laible and Hamann (6). 

Dissolve the OH-indole in ethanol (0.14 M in 50 ml) and add 28 ml dimethylsulfate and 1.2 g Na hydrosulfite. Add slowly with stirring and cooling (under N2 if possible) 12 g NaOH dissolved in 26 ml water (keep temperature at 20-25°). Heat to 70° for one-half hour, cool and dilute with an equal volume water. Extract the yellow oil into ether-benzene and dry, filter, and evaporate in vacuum to get the methoxy-indole. 

Figure 2 Encapsulation as a function of ethanol concentration. Oligonucleotides were added to distearoyl-phosphatidyl-choline/cholesterol/l-0-(2 -(co-methoxy-poly-ethylene-glycol)succinoyl)-2-iV-myristoyl-sphingosine /1,2-dioleoyl-3-dimethylam-monium propane liposomes in varying concentrations of ethanol at an initial oligonucleotide-to-lipid ratio of 0.24mg/mg. Abbreviations AS, antisense oligonucleotide %EtOH(v/v), percentage of ethanol in volume/volume.

Nucleophilic-displacement reactions constitute some of the earliest known methods for the preparation of deoxyhalogeno sugars. A variety of leaving groups have been used, including sulfonyloxy (usually jP-tolylsulfonyloxy or methylsulfonyloxy), halide, triphenyl-methoxy (trityloxy), acetoxy, phosphate, and nitrate. As Barnett has surveyed the reactions in Volume 22 of this Series,1 this subject will not be discussed comprehensively in the present Chapter instead, only some general comments will mainly be made that will also be relevant to later discussions. 

To design a supercritical fluid extraction process for the separation of bioactive substances from natural products, a quantitative knowledge of phase equilibria between target biosolutes and solvent is necessary. The solubility of bioactive coumarin and its various derivatives (i.e., hydroxy-, methyl-, and methoxy-derivatives) in SCCO2 were measured at 308.15-328.15 K and 10-30 MPa. Also, the pure physical properties such as normal boiling point, critical constants, acentric factor, molar volume, and standard vapor pressure for coumarin and its derivatives were estimated. By this estimated information, the measured solubilities were quantitatively correlated by an approximate lattice equation of state (Yoo et al., 1997). 

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