Oxidants greenest

The CL monomer is obtained by the traditional Baeyer-Villiger reaction, starting from cyclohexanone as substrate. However, this synthetic route is not environmentally friendly, which has involved the development of two greener routes (1) use of a peroxycarboxylic acid (such as 3-chloroperbenzoic acid or peracetic acid) in dichloromethane at 40 ° C, and (2) use of hydrogen peroxide as oxidizer and zeolite/tin catalysis.The second process is considered the greenest because the main by-product is exclusively water and the tin-impregnated zeolite is an environmentally friendly catalyst. Nowadays, CL is produced by several manufacturers like BASF (USA), Perstorp (UK), and Daicel Chemical Industries Ltd. (Japan). 

Air is the greenest oxidizing agent. There is currently much research effort aimed at achieving the oxidation of aicohois under mild aerobic conditions. 

Several groups have successfully utilized molecular o>q gen as the sole oxidant in aerobic Pd-catalyzed biatyl CDC reactions. These reactions are probably the greenest CDC reactions that exist right now due to the fact that using O2 or air as the oxidant is inexpensive and makes water as a final byproduct. Most of these 02-oxidized reactions take place in an acidic environment and at temperatures ranging anywhere from 55-120 °C. 

Using O2 as the only oxidant is, to date, the greenest condition for the synthesis of biatyls via GDC however, several studies have shown that catal5dic amounts of a metal oxidant can be used along with O2 as a terminal oxidant (Scheme 6.5). °... 

The fuel cell represents another electrochemical reaction. The fuel cell requires a constant source of fuel, usually hydrogen, in order to continue to produce electricity. The electrochemical reaction involves the oxidation of hydrogen to produce water, representing the greenest energy opportunity (except that the production of hydrogen to power the fuel cell may not be as green as desired). 

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