Mixed reagent

The method has been applied to the reduction of cholestanone. Red uction of this ketone with the mixed reagent and no additional ketone gave 17% of the a-epimer under the equilibration conditions only 3p-ol and unreduced ketone are obtained. Reduction of coprostanone with the mixed reagent gives 94% of the 3a-ol. ... 

Even mixed reagents with Lewis acids attack at the less-substituted position, indicating dominance of the nucleophilic bond making over the electrophilic component of ring opening.38... 

As a rule, the order of mixing reagents is of no importance. The addition of sulfur or selenium into the reaction mixture in a last stage makes it possible to obtain corresponding derivatives. 

Figure 2.5. Analytical manifolds for the determination of phosphate by flow injection analysis (a) and reverse flow injection (b). The symbols S, M, and A are the seawater, mixed reagent, and the ascorbic acid solutions. The pump injection valve and detector are represented by P, I, and D, respectively. W = waste. From [177]... 

The determination of the orthophosphate was carried out by using the automated systems described by the Technicon Instruments Corporation. The manifolds used are shown in Fig. 12.3. The procedures referred to below as methods I and II are Technicon industrial methods Nos. 94-70W and 155-71W, respectively. Method I includes ascorbic acid alone for the reduction of the molybdophosphoric acid whereas in method II the mixed reagents ascorbic acid, sulphuric acid, ammonium molybdate and antimony potassium tartrate are used. Method I is intended for use for high levels of phosphorus (up to lOpg ml4) and method II for low levels (less than 0.5pg ml4). The wetting agent (Levor IV) used in order to obtain a smooth bubble pattern, is present in the ascorbic acid reagent line for method I whereas it is added externally Fig. 12.3) in the water line (0.5pg ml4 of Levor) in method II. 

Silylated primary allylic amines, e.g. CH2=CHCH2N(SiMe3)2, are produced from allylic chlorides and the mixed reagent AgI/LiN(SiMe3)2205. The formation of allylic amines from olefins by the ene reaction is shown in equation 77. The ene adducts 205 from bis(2,2,2-trichloroethyl) azodicarboxylate are converted into 206 by zinc dust in acetone/acetic acid206. 

Maintain the same overall polymer dosage and relative rate of addition (rate per unit volume). For continuous polymer addition this specifies the same mixing/reagent addition time. 

Gorl cr Hamon Levisallcs Wagnon 7. Chem. Soc., Chem. Commun. 1973, 88. For another useful mixed reagent see Ledlie Miller 7. Org. Chem. 1979, 44, 1006. 

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