Genation over

HFC-245eb can be prepared from hexafluoropropene (HFP) by the sequence shown in eq 20 in which the HFP is hydrogenated over a Pd/C catalyst to HFC-236ea. This is dehydrofluorinated over carbon to HFC-1225ye, which is then hyro-genated over a Cu/Pd/C catalyst to HFC-245eb [74],... 

Bis-silyl ketene acetals devoid of -protons undergo a clean silatropic ene reaction with singlet oxygen (see Sections 2.3.2.1.3.ii and 2.3.2.4.3.U) to generate the a-silylperoxy sUyl ester quantitatively. Treatment with methanol affords the a-hydroperoxy acid, also quantitatively (Scheme 23). Hy genation over platinum reveals the a-hydroxy acid, once again, quantitatively. Despite this encouragement die substrate limitation is severe. 

Oxidative Dehydrogenation. Specific reviews deal with oxidative dehydro-genation of lower alkanes, particularly over vanadium oxide-based cata-... 

Bengough and Sharpe (26) measured the rate of dehydrohalo-genation of laboratory-prepared samples in which catalyst residues were removed by purification. Nitrogen gas was swept over the degrading solution and thereby entrained the evolved HCl, which was measured analytically. An increased rate of HCl loss was noted with lower molecular weight polymers and was proportional to the number of moles of polymer present. This result suggests that the loss of HCl is connected in some way to the concentration of polymer chain ends. 

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