Towards the 150th anniversary of the Markovnikov's rule.

The Markovnikov rule, known to every student of organic chemistry, was formulated 150 years ago, in 1869. During its long history (almost as long as the history of organic chemistry itself) attitudes towards this famous statement of chemical reactivity have evolved from indifference up to the 1930s, through common acceptance as a useful educational paradigm with a marginal use in research until the 1990s, to its vigorous re-launch as an important marker of regioselectivity in the last few decades. The unexpected new popularity of the classical rule is accounted for by a rapid expansion of catalytic addition reactions and their critical importance as highly effective atom-economical, regioselective methods in modern organic synthesis. Historical sketch of the life and achievements of Vladimir Markovnikov is included to reveal a very wide scope of interests and prophetic predictions on the structure, reactivity, selectivity, stereochemistry, and other key issues of organic chemistry.