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The anti-Markovnikov rule can be illustrated using the addition of hydrogen bromide to isobutylene in the presence of benzoyl peroxide or hydrogen peroxide. The reaction of HBr with substituted alkenes was prototypical in the study of free-radical additions. Early chemists discovered that the reason for the variability in the ratio of ...
In 1869, a Russian chemist named Vladimir Markovnikov demonstrated that the addition of HBr to alkenes usually but not always resulted in a specific orientation. Markovnikov's rule, which stems from these observations, states that in the addition of HBr or another hydrogen halide to an alkene, the acidic proton will add to the less substituted carbon of the double bond. [3]
Reformatskii's work, which used the zinc compounds from alpha-bromoesters, led to the discovery of a synthetic reaction (the Reformatskii reaction) that is still used today. Zaitsev's Rule was reported in 1875, and appeared just as his nemesis, Markovnikov, (who had made a prediction which the rule contradicts) was taking the Chair at Moscow ...
Vladimir Markovnikov was born on December 22, 1837, in Chernorechye near Nizhny Novgorod, Russian Empire (now Dzerzhinsk, Nizhny Novgorod Oblast, Russian Federation). Soon after his birth, his father retired and settled in a family estate received as a dowry from his wife's family at marriage, in the village of Ivanovo, Knyagininsky district of the Nizhny Novgorod province, where Markovnikov ...
Products in chemistry that follow this rule are considered Markovnikov products and those that did not are considered anti-Markovnikov products. [88] Markovnikov's rule was an early example of regioselectivity in organic synthesis and the modern understanding of it continues to be important in the chemical industry, where catalysts have been ...
Russian President Vladimir Putin basked in a victory early Monday that was never in doubt, as partial election results showed him easily securing a fifth term after facing only token challengers ...
To Pipes, not just Stalinism was a mere continuation of Leninism, but more to it, "the Russia of 1917–1924 was no less 'totalitarian' than the Russia of the 1930s"; Pipes compared Lenin to Adolf Hitler and described the former as a precursor of the latter: "not only totalitarianism, but Nazism and the Holocaust has a Russian and a Leninist ...
THE HAGUE (Reuters) -The United Nations' highest court will rule on Friday whether it will hear a case in which Ukraine has accused Russia of violating international law by saying its invasion was ...