Tetra bromoethane

Conversion of haloperidol to reduced haloperidol (a secondary alcohol) Glutathine dependent reduction of disulfiram to deithyldithiocarbamate Thioredoxin dependent of sulindac to sulindac sulfide DT diaphorase reduction of menadione to hydroquinone Conversion of pentabromoethane to tetra bromoethane (releasing free bromide ion)... 

Fig. 10ar-e. Time distribution of [3H]PVP and [14C]sorbitol for solutions described in Fig. 5 with the inclusion of trace amounts of [14C]sorbitol in the bottom solution. The boundary was formed in plastic tubes (10 x 60 mm) between solutions of 19 mm in column height. A dense solution of tetra-bromoethane was placed into the bottom part of the tube. The contents of the tube were fractionated at various times by displacement with tetrabromoethane and the distribution of [3H]PVP ( ) and [UC]sorbitol (O) was determined. The position of the original boundary is indicated by a dotted line. The ordinate represents the proportion of the radioactivity (in percent) in the sample, Cv as compared to that originally present below the initial boundary C0. The abscissa represents the ratio of the distance along the tube to the total length of the tube which was approx. 38 mm. The time of the fractionation was a) 11 min, b) 73 min, c) 134 min, d) 251 min, e) 490 min 47)... 

The alkynes behave in many ways as if they were doubly unsaturated alkenes. For example, bromine adds to ethyne in two stages —first to give trans-1,2-dibromoethene by antarafacial addition, and finally to give 1,1,2,2,-tetra-bromoethane ... 

Density Measurements. The measurements were made according to the method of Archimedes. As the amount of sulfide was limited to 0.2 or 0.3 gram, the resulting loss of precision was offset by choosing a liquid whose density was as close as possible to those of the sulfides studied. The density of 1,1,2,2-tetra-bromoethane, the liquid chosen, was determined in advance as a function of temperature. The sulfides, placed in a special weighing boat, were immersed under vacuum in the apparatus shown in Figure 2. Under these conditions, the densities of the sulfides were determined with a precision of 0.2%. 

A necessary component of the balanced-density slurry solvent was tetra-bromoethane, which has a density higher than that of silica. However, it decomposes easily and its toxidty is a major drawback, espedally for commercial column production. Therefore alternatives were sou t quickly. In 1972, Kirkland (4) described a technique in which silica particles were suspended in an aqueous ammonium hydroxide solution, and in 1974 Asshauer and Haliisz (S) reported success with slurries based on high-viscosity solvents. 

Acetone, bromoethane, butane, chloroethane, 2-chloropropane, 1,3-cyclopenta-diene, dibromodifluoromethane, 1,1-dichloroethane, 1,1-dichloroethene, 1,2-di-chloro-l,l,2,2-tetra luoroethane, diethylether, dimethoxymethane, dimethylpro-pane, 1,3-epoxypropane, ethyl formate, glyoxal, methyl acetate, methylbutane, methyl formate, methylpropane, -pentane, propanal. 

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