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Such reactions are said to be anti-Markovnikov, since the halogen adds to the less substituted carbon, the opposite of a Markovnikov reaction. 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 ...
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]
In terms of regiochemistry, hydroboration is typically anti-Markovnikov, i.e. the hydrogen adds to the most substituted carbon of the double bond. That the regiochemistry is reverse of a typical HX addition reflects the polarity of the B δ+-H δ− bonds. Hydroboration proceeds via a four-membered transition state: the hydrogen and the boron ...
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Dalgona milk tea, milk tea sweetened with traditional Korean dalgona, a honeycomb-like toffee [19] In Britain, when hot tea and cold milk are drunk together, the drink is simply known as tea due to the vast majority of tea being consumed in such a way. The term milk tea is unused, although one may specify tea with milk if context requires it ...
A Flowering tea, green tea with jasmine flowers.. Teas blended with other additives were developed in ancient China. As far back as the Jin dynasty (266–420), ground up tea leaves were boiled with scallions, ginger, and orange peels as reported in the Guangya dictionary (c. 3rd century CE). [2]
In organic chemistry, Zaytsev's rule (or Zaitsev's rule, Saytzeff's rule, Saytzev's rule) is an empirical rule for predicting the favored alkene product(s) in elimination reactions. While at the University of Kazan , Russian chemist Alexander Zaytsev studied a variety of different elimination reactions and observed a general trend in the ...
In organic chemistry, a substituent is one or a group of atoms that replaces (one or more) atoms, thereby becoming a moiety in the resultant (new) molecule. [1] ( In organic chemistry and biochemistry, the terms substituent and functional group, as well as side chain and pendant group, are used almost interchangeably to describe those branches from the parent structure, [2] though certain ...