Acids as proton donors

Bronsted theory a theory of acids and bases that defines acids as proton donors and bases as proton acceptors. 

An acid is a substance from which a proton can be removed. (Some chemists describe Brqnsted-Lowry acids as proton-donors. )... 

A very effective tosylamide cleavage seems to be possible by the cooperative action of the electro-generated anthracene anion radical as electron transfer agent and of ascorbic acid as proton donor and additional reducing agent (Eq. (97))... 

The use of aliphatic and aromatic alcohols, amines, and carboxylic acids as proton donor molecules with DTBN reveals that whereas the X-H protons are shifted to low frequency by the radical the C-H protons, other than X-H, are moved to high frequency (223) (Table X). These high frequency shifts are shown to be characteristic of protic molecules and demonstrate conformational or geometrical dependences. Thus, protons lying on a zig-zag path from the -OH or -NH... 

In Chapter 2, we will concentrate on two definitions of acids and bases the Brpnsted-Lowry definition, which describes acids as proton donors and bases as proton acceptors, and the Lewis definition, which describes acids as electron pair acceptors and bases as electron pair donors. 

A useful system for indirect electrolysis of sulfonamides was reported to be anthracene as mediator in the presence of ascorbic acid as proton donor [260]. 

Earlier definitions of acids and bases as species producing respectively hydrogen ions and hydroxyl ions are only valid in aqueous solution. The concept of Br nsted and Lowry, while extending the classical definition, does not exclude the treatment of Arrhenius for aqueous media. The extended view regards acids as proton donors and bases as proton acceptors regardless of whether substances concerned are ionic or neutral. A terse summary of this definition may be given as follows... 

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