Order of migration

Following the radical pathway" the next step is a homolytical cleavage of the N-R bond. The rearrangement to yield the tertiary amine 3 then proceeds via an intermediate radical-pair 4a. The order of migration is propargyl > allyl > benzyl > alkyl ... 

In the mildest of these reactions the hydroxylamine is refluxed in ether over phosphorus pentachloride and the same order of migration aptitudes is observed as in the pinacol rearrangement. The range in... 

Electrophoresis of a mixture of the dinucleotides ApC and ApU at pH 3.5 separates two components. Identify these and explain the order of migration. Be as quantitative as possible. 

The order of migration of the standard lipids during chromatography depends primarily on polarity. The less polar the lipid, the greater its affinity for the nonpolar solvent (compared to the polar silica gel) and hence the greater the migration. 

The key operational parameter in free-solution capillary electrophoresis is the pH of the running buffer, as the electroosmotic flow and ionization of the analyte can be regulated by this variable. The role of buffers in capillary electrophoresis has been discussed in detail, with emphasis on buffer concentration, buffer type, and pH effects [10]. The effect of organic solvents on separation and migration behavior has been studied for dipeptides [11] and somatostatin analog peptides [12]. The order of migration as well as the selectivity may be manipulated by organic modifiers in... 

Will the three compounds in Figure 4-11 be clearly separated from one another by electrophoresis at pH 11 If so, describe the electrode toward which they will migrate and the order of migration. If not, why not ... 

In the case of unsymmetrical glycols the product formation depends mainly on which OH group is lost to leave behind the most stable carbocation, and thereafter which group migrates. The order of migrating aptitude is Ar > H > R. 

If the y-carbon in either of the alkyl groups is substituted, the order of migration of the y-hydrogen is found to be tertiary > secondary > primary, and the rearrangement preferentially involves the larger alkyl groups. 

The paper and the electrode chambers contain 0.05 M or 0.1 M ammonium formate made pH 3.5 with 88% formic acid. With a voltage gradient of 100 volt cm the nucleotides are separated in 1 to 3 hr, Up having run a distance of approximately 30 to 90 cm respectively. The order of migration towards the anode is Up (fastest), Gp, Ap and Cp. Except for Gp the 2 and 3 isomers migrate together. 

Antifreeze glycoprotein is a collective name for a family of at least eight closely related glycoproteins that account for a major fraction of the protein in the blood serum of certain Antarctic fishes. The glycoproteins have been numbered according to the order of migration of... 

Electrophoresis at pH 6.4 using a citrate buffer is performed when an abnormal band is noted on alkaline Hb electrophoresis. Agarose is the preferred medium, with Acid Violet the preferred stain. Figure 31-10 shows the same Hb variants performed on agarose electrophoresis at pH 6.4 and stained with Acid Violet. The order of migration (cathode to anode, fastest to slowest) is Hb F, Hb A, Hb S, and Hb C. Hemoglobins D, G, I, J, O, A2, and E co-migrate with Hb A. 

Figure 6.9. Separation of a mixture of estrogens by incremental multiple development with variable (A) and fixed (B) solvent entry position, and by multiple chromatography (C). A nine step sequence with the mobile phase cyclohexane-ethyl acetate (3 1, v/v) was used for (A) and (B) and seven 7 cm developments for (C), all on a silica gel HPTLC layer. The estrogens, in order of migration, are 17p-dihydroequilenin,...

Order of migration capability (Polynov) Components Relative mobility of macrocomponents by Cl... 

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