Electrolytic cleavage, 3 groups

Electrolysis, Me4N Cl , 5°, 65-98% yield. " Acylation of a tosylated amine with BOC or benzoyl reduces the potential required for electrolytic cleavage so that these aryltosyl groups can be selectively removed in the presence of a simple tosylamide. °... 

Electrolytic cleavage, 3 (review) of benzamides, to form amines, 356 of benzoate esters, to form alcohols, 102 of benzyl carbamates, to form amines, 336 of benzyl carbonates, to form alcohols, 109 of benzyl esters, to form carboxyl groups, 251... 

An electrolytic cleavage of such a bond in a convenient potential interval occurs only when the bond is activated, e.g., by an adjacent carbonyl or azomethine group. 

Electrolytic cleavage, of acyl-type protecting groups 670, 671, 676 of amines 437... 

Three selective methods to remove protective groups are receiving much attention assisted, electrolytic, and photolytic removal. Four examples illustrate assisted removal of a protective group. A stable allyl group can be converted to a labile vinyl ether group (eq. 4) a /3-haloethoxy (eq. 5) or a /3-silylethoxy (eq. 6) derivative is cleaved by attack at the /3-substituent and a stable o-nitro-phenyl derivative can be reduced to the o-amino compound, which undergoes cleavage by nucleophilic displacement (eq. 7) ° ... 

Dioxacycloalkanes are cyclic acetals that are used frequently as protective groups. Substituted derivatives have been synthesized to achieve easy removal. Simplest of all, the 4-phenyl-1,3-dioxolane has not been used commonly because cleavage needs electrolytic conditions. A mild hydrogenolysis method was developed in 1997 to make this protective group more popular (Scheme... 

The ZPC of an unaltered mixed oxide, silicate, or phosphate in a system devoid of specific electrolytes other than the PDI is approximately the average of the IEP(s) s of its component oxides weighted on an atomic (cation) basis. Account must be taken of the correct cation coordination, cleavage and morphological habit, hydration state, and structural modification produced by abrasion. Experimental and calculated ZPC s for a group of silicate and phosphate minerals are compared in Figure 13 to show the accuracy to be expected in prediction. 

A non-planar transient complex was also proposed to account for the behaviour of the radical anions of halobenzoic acids423. The cleavage rates of these anions were measured using a photoelectrochemical method based on photoelectron injection from a metal into an electrolyte solution. The rates depend on the nature of the halogen and its position in the ring relative to the carboxylate group, increasing in the series F < Cl < Br and meta < para < ortho (Cl, Br) and meta < ortho < para (F). 

In contrast to phosphine oxides, whereby the phosphoryl group is reduced, the reduction of phosphonium salts involves cleavage of a P—C bond. There are several ways this can be achieved, including base-induced cleavage, thermal decomposition, hydride or electrolytic reduction.2... 

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