Selenium tetrachloride with pyridine

When the solvent takes part in acid-base phenomena, the reactions are usually displacement reactions. Considering only acid-base reactions, solvents may be divided into three classes (1) those that are ordinarily inert toward acids and bases, e.g., benzene, carbon tetrachloride, and chlorobenzene (2) those that are ionizable, e.g., water, ammonia, sulfur dioxide, phosgene, and selenium oxychloride (3) those that do not ionize but do react with acids and bases, e.g., ether and pyridine. If we consider the neutralization of boron trichloride by triethylamine in the three types of solvents, we find that the net result may be the same as when the neutralization occurs in the absence of a solvent ... 

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