Proton donating group

Thus, the functionalized anilines 85 and 86 are obtained in 71-89% yield starting from diiodoanUines 87 and 88 (Scheme 6). Other proton-donating groups like hydroxy groups (equation 25), acids, amides or benzylic alcohols are also compatible with this approach. 

Tarantino, R., Bishop, E., Chen, F.-C., Iqbal, K., and Malick, AW Methyl-2-pyrrolidone as a cosolvent relationship of cosolvent effect with solute polarity and the presence of proton-donating groups on model drug compoundspharm. Sci., 83,1213-1216, 1994. 

Kato, S. Nonoyama, N. Tomimoto, K. Mase, T. Non-cryogenic metalation of aryl bromides bearing proton donating groups formation of a stable magnesio-intermediate. Tetrahedron Lett. 2002, 43, 7315-7317. 

Lehmann, J, Schlesselmann, P, Location of a proton-donating group at the re-face of a (i-D-galactosidase-bound, diastereotopic substrate, Carbohydr. Res., 113, 93-99, 1983. 

The relation between the extent of solubilization and the structures of solubi-lizate and surfactant-polymer complex is not completely clear. Aromatic hydrocarbons appear to be more highly solubilized than aliphatic hydrocarbons by complexes of anionic surfactants and hydrophilic polymers with no proton-donating groups, such as polyvinylpyrrolidone, but the nature of the forces involved is not clear. Some cationic surfactant-polymer complexes are broken by the solubilization of aromatic hydrocarbons. It has been suggested that structural compatibility between solubilizate and polymer may be a factor and that the function of the surfactant is to increase the hydrophilic character of the polymer and to promote contact between polymer and solubilizate (Saito, 1967). 

The fact that the reaction is stereospecific suggests that a specific enzyme group is responsible for protonation of the enolate product (if the enolate were released and protonated in solution, this would give rise to racemization). The proton-donating group may be lysine, based on the structure of pyruvate kinase. 

A soln. of DL-methionine, 3 moles diethyl azodicarboxylate, ethanol, and water stirred 3 hrs. at room temp. DL-methionine sulfoxide. Y 97,5%. - The reaction is dependent on the presence of a proton-donating group. F. e. and limitations s. R. Axen, M. Chaykovsky, and B. Witkop, J. Org. Chem. 52, 4117 (1967). 

Aprotic/Protic Aprotic solvents (also commonly called inert) have very little affinity prottms and are inc able to dissociating to give piotcms. Aprotic solvents are also called indifferent, non-dissociating, or non-itmizing. Protic solvents contain proton-donating groups. 

Hydrogen bonding involves the interaction between a proton donating group (Ri—X—H) and a proton acceptor (Y—R2) and may be described sdiematically by... 

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