Ceric ammonium nitrate processes

The /7-nitrophenyl ether was used for the protection of the anomeric position of a pyranoside. It is installed using the Konigs-Knorr process and can be cleaved by hydrogenolysis (Pd/C, H2, AC2O), followed by oxidation with ceric ammonium nitrate (81-99% yield). ... 

This technique is based in the fact that when cellulose is oxidized by ceric salts such as ceric ammonium nitrate Ce(NH4)2(N03)6 free radicals capable of initiating vinyl polymerization are formed on the cellulose. However, the possibility remains that the radical formed is an oxygen radical or that the radical is formed on the C-2 or C-3 instead of the C-6 carbon atom. Another mechanism, proposed by Livshits and coworkers [13], involves the oxidation of the glycolic portion of the an-hydroglucose unit. Several workers [14,15], however, have found evidence for the formation of some homopolymer. In the ceric ion method free radicals are first generated and are then capable of initiating the grafting process [16-18]. 

Graft copolymerization of methylmethacrylate onto paper wood pulp using ceric ammonium nitrate as the initiator has been studied. Different experimental conditions have been used, including both water and water-organic solvent systems. The effects of composition of the grafting medium and grafting temperature on the grafting process are examined. 

The N-desilylation of 1-trimethylsilyl- or 1 -(// rt-butyldimethylsilyl)-2-azctidinones is a commonly used process in 2-azetidinone chemistry. The leri-b11toxycarbonyI group is readily removed with trifluoroacetic acid, while the 4-methox-yphenyl protecting group is conveniently removed by ceric ammonium nitrate, or anodic oxidation (Scheme 87). 

Lee W-J, Park H-S, Lee S-I, Sohn H-C. Effect of ceric ammonium nitrate (CAN) additive in HNO3 solution on the electrochemical behavior of Ruthenium for CMP processes. J App Electrochem 2004 34 119-125. 

Epoxides can be converted directly to episulfides by treatment with NH4SCN and ceric ammonium nitrate.Diazoalkanes, treated with sulfur, give episulfides.It is likely that R2C=S is an intermediate, which is attacked by another molecule of diazoalkane, in a process similar to that shown in 16-46. Thioketones do react with diazoalkanes to give episulfides.Thioketones have also been converted to episulfides with sulfur ylids.Carbenes, such as the dichlorocarbene from CHCI3 and base, react with thioketones to give an... 

Another method of graft copolymer synthesis is a combination of microwave-based and conventional synthesis, i.e. using both microwave radiation as well as a chemical free radical initiator (e.g. ceric ammonium nitrate) together. This process is referred to as microwave assisted synthesis [47]. Although it yields a higher percentage grafting than the microwave initiated synthesis, the rehability of the synthesis process is low. 

The upper echelons who were running the show were serious about this hydroquinone thing. Therefore, this product Z-7.2, that should have been entered into human evaluation, was instead processed further by the substitution of a t-BOC on the amine group, oxidation to the quinone with ceric ammonium nitrate, reduction to the hydroquinone with dithionite, and finally deprotection of the blocking t-BOC group by hydrochloric acid. The final product,... 

Lee, W.-J., Park, H.-S., 2004. Development of novel process for Ru CMP using ceric ammonium nitrate (CAN)-containing nitric acid. Appl. Surf. Sci. 228, 410—417. 

The NO3 radical has been produced via photolysis of solutions of ceric (IV) nitrates in mixtures of water with nitric acid (HNO3) [2-7] and acetic acid [8] as well as pure HNO3 [8]. Using flash photolysis of ceric ammonium nitrate (CAN) (NH ),Ce(N03) solutions, Martin and co-workers [2-5, 8] first postulated the primary photochemical process ... 

Even shorter, and certainly less conventional, is the synthesis of (—)-tashiromine ent-929) by MacMillan s group (Scheme 121). " This route rehed on the ortho-selective intramolecular a-arylation of the pyrrole-aldehyde 979 mediated by the chiral amine catalyst 980 in conjunction with ceric ammonium nitrate as a single-electron oxidant in a process that MacMillan has termed organo-SOMO catalysis. The reaction is thought to proceed via an imine intermediate that undergoes oxidation to the radical... 

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