1-Adamantyl free radical

Further alkylations involving the 1-adamantyl free radical... 

In addition to the reactions discussed in the previous section, the free radical produced photochemically from PhI(02CAd)2 reacted with alkyl or aryl or cyclic disulphides to afford the corresponding adamantyl sulphides in good yield [79] ... 

A reaction kettle was charged with propylene glycol monomethyl ether acetate (5.1 g) and propylene glycol monomethyl ether (3.4 g) and then heated to 80°C. This mixture was next treated dropwise with the Step 1 product (2.7 g), 3-hydroxyadamantane methacrylate (4.7 g), 2-methyl-2-adamantyl methacrylate (7.0 g), y-butyrolactone methacrylate (6.8 g), and the free radical initiator V-601. Thereafter the reaction proceeded for 2 hours at 80°C and was then cooled and poured into a 720 ml mixture of hexane containing 80 ml of EtOAc. The precipitate was collected, and 18 g of product were isolated having a Mw of 10,700 daltons with a polydispersity of 1.81. 

Adamantyl haUdes, reactions of 677 p-(l-Adamantyl)phenols, synthesis of 606, 607 Aerophobin-1, biosynthesis of 1315, 1316 Aeroplysinin-1, synthesis of 1327, 1328 Aerothionin, biosynthesis of 1315, 1316 Ageing, free-radical theory of 140, 141 Agent Orange 12... 

Radical alkylation of heteroaromatic bases. Carboxylic acids undergo decarboxylation to generate free radicals, which can be captured by heterocycles. Thus 2-(l-adamantyl)-4-cyanopyridine is obtained in 88% yield from 1-adamantylcar-boxylic acid and 4-cyanopyridine. 

Cheves Walling commented on the high chloride/bromide ratio obtained from adamantane - - O3 - - CBrCla, unusual in a radical-abstraction process. An even higher ratio has, however, been reported (J. I. G. Cadogan, D. H. Hey, and P. G. Hibbert, J. Chem. Soc. 1965, 3939) for attack by a well-authenticated free radical in the presence of oxygen hence, our interpretation of this reaction as proceeding via 1-adamantyl radicals stands. 

Free-radical halogenation of adamantane has been examined. By product analysis of halogenations in the presence and in the absence of oxygen it was possible to conclude that (a) the 1-adamantyl radical is more readily formed, (b) the 1-adamantyl radical has a longer lifetime, and (c) 1-adamantyl radical is less selective in halogen abstraction than the 2-adamantyl radical. This... 

Free-radical copolymerizations of 2-acrylamido-2-methylpropanesulfonate (AMPS) and methacrylamides A -substituted with bulky hydrophobes of cyclic structures yields random copolymers (see Scheme 1) that form unimer micelles in aqueous solution independent of the concentration [22], Such hydrophobic methacrylamides include Y-cyclododecylmethacrylamide (CdMAm) [24], A -(l-adamantyl)methacrylamide (AdMAm) [24], and A -(l-naphthylmethyl)methacrylamide (1-NpMAm) [25]. 

The interaction between two adjacent bulky groups can depend on steric factors which are not necessarily related to the stability of the radicals produced on homolysis. It is estimated from linear free energy relationships that only 65-70% of the ground-state strain energy is relieved in the transition state for homolysis of a bond between two quaternary centres (Ruchardt and Beckhaus, 1980, 1986). Thus steric constraints to delocalization in the radicals produced may persist. A pertinent example is 2,3-di(l-adamantyl)-2,3-dimethylbutane [123] which has four such centres, linked by the long C-C bonds characteristic of this sort of structure. The strongest... 

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