Zaïtsevs

Zaïtsevs is a term that can refer to several distinct entities, primarily associated with Russian surnames and, in chemistry, a rule of elimination. The most common usage refers to the surname Zaïtsev, a Slavic surname of Russian origin. Notable individuals with this surname include Aleksandr Zaïtsev, a 19th-century Russian chemist, and various athletes and public figures. The surname itself is derived from the word "zayats," meaning "hare."

In organic chemistry, Zaïtsev's rule (also known as the Zaitsev rule or Saytzeff's rule) is a guideline for predicting the outcome of elimination reactions. It states that in an elimination reaction that can produce multiple alkenes, the more substituted alkene (the one with more alkyl groups attached to the double bond carbons) will be the major product. This is because a more substituted alkene is generally more thermodynamically stable. This rule is particularly useful in understanding reactions like dehydrohalogenation.

There is also a concept of "zaïtsev product" in chemistry, which directly refers to the more substituted alkene predicted by Zaïtsev's rule. Conversely, the less substituted alkene is referred to as the Hofmann product, following Hofmann's rule, which typically applies in different reaction conditions, often with sterically hindered bases. The application and exceptions to Zaïtsev's rule are important topics in organic chemistry education and research.