Reduction agents

By application of the Leuckart-Wallach reaction,amines 2 can be alkylated with a carbonyl compound 1 formic acid is used as reductive agent, and is in turn oxidized to give carbon dioxide. 

Other fields Friction reduction agents, dispersants, adhesives, fiber dressers... 

Usually metal-free phthalocyanine (PcH2) can be prepared from phthalonitrile with or without a solvent. Hydrogen-donor solvents such as pentan-l-ol and 2-(dimethylamino)ethanol are most often used for the preparation.113,127 128 To increase the yield of the product, some basic catalyst can be added (e.g., DBU, anhyd NH3). When lithium or sodium alkoxides are used as a base the reaction leads to the respective alkali-metal phthalocyanine, which can easily be converted into the free base by treatment with acid and water.129 The solvent-free preparation is carried out in a melt of the phthalonitrile and the reductive agent hydroquinone at ca. 200 C.130 Besides these and various other conventional chemical synthetic methods, PcH2 can also be prepared electrochemically.79... 

Walter, M. and Hakkinen, H. (2006) A hollow tetrahedral cage of hexadecagold dianion provides a robust backbone for a tuneable sub-nanometer oxidation and reduction agent via endohedral doping. Physical Chemistry Chemical Physics, 8, 5407-5411. 

R. M. Kowalik, I. Duvdevani, K. Kitano, and D. N. Schulz. Drag reduction agents for hydrocarbon solutions. Patent US 4625745,1986. 

Interestingly, in some cases the IL itself can act as the reductive agent. Spherical metal silver NPs were prepared in a hydroxyl-functionalized IL (2) (entry 30, Table 1.1) [17]. In this case, the hydroxyl moiety of the IL plays a reductive role, being oxidized to the corresponding aldehyde. In a similar manner, for Au(III) precursors, the imidazolium cation itself can act as a reducing agent to yield prismatic particles in BMI.PF6 with a very broad size range of diameter 3-20 pm and thickness... 

Fig. 9.4 The enzyme RNase can be unfolded by reduction agents (urea and mercaptoethanol). Oxidative removal of the reduction agents causes the molecule to take up its three-dimensional structure again it regains almost its full enzymatic activity...

Under similar conditions, reactions between pyrrolidine derivatives 632 and MTAD proceed much more slowly and less cleanly with formation of a polymeric material. When the reaction is stopped before 50% conversion is reached, starting compound 632 is isolated as the main component (c. 40%) and compound 637 as a minor product (10-14%). Mechanistically, the most difficult problem lies in the fact that a reduction step has to be involved and no particular reduction agent is present. A proposed mechanism is shown in Scheme 103. The pathway includes a Cannizzaro-type hydride transfer between dipole 633 and product 634 (keto tautomer), resulting in the formation of the iminium derivative 635, which might be responsible for the polymeric material, and hydroxy derivative 636, the direct precursor of the final products 637. The low experimental yield of 637 could be explained by this mechanism <2003EJ01438>. 

Reduction of gem-dibromocyclopropanes has been achieved by a variety of reducting agents to give either monobromocyclopropanes or cyclopropanes,... 

Reactions other than those discussed in subsections 1.3.1. to 1.3.4. are presented here. Transformations of nitrile oxides by the action of reductive agents and... 

In many cases also the reduction agent itself influences the result of the reduction, especially if it is bulky and the environment of the function to be reduced is crowded. A more detailed discussion of stereochemistry of reduction with hydrides is found in the section on ketones (p. 114). 

When fluorescent detection is used, the mobile phase contains zinc chloride as the reduction agent for vitamin K derivatization. The most used mobile phases are methanol and dichloromethane or water. 

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