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1)HOW CAN WE DECIDE WHETHER A GIVEN REACTION PROCEEDS VIA ELECTROPHILIC MECHANISM OR NUCLEOPHILIC MECHANISM ?

2) Is there any difference between Markownikoff rule and Saytzeff rule ?

Plz reply

sti

markovnikov concerns addition.......... saytzeff concerns dehydrohalogenation. as 4 u r 1st question after the carbocation is formed if electrophile attacks first then it will proceed in electrophilic mechanism. otherwise nucleophilic way

sboosy

Markovnikoff rule and saytzeff rule are entirely two differnent things . first one says addition of A(+charged )B(-charged)
to alkene follows the rule that the negatively charged part adds to the carbon having lesser number of hydrogens
this ofcourse is disobeyed as u ll probably know in presence of peroxide
in case of dehydrohalogenation we usually talk of saytzeff and hoffmann rule
according to saytzeff the more substituted alkene is the major product
but if the product so obtained is sterically compressed then
less substitued alkene or the hoffmann product may be formed

dream

what is Hoffmanns rule

more replies for 1st question

rabindra8

Markovnikov's Rule is used for addition reaction where as Saytzeff Rule is used for elimination reaction. Hofmann rule is also used for elimination reaction and this rule is applicable if leaving group is cationic. According to this rule less substituted alkene will be the major product .i.e. hydrogen is removed that

carbon which bears more number of hydrogen atoms. When quaternary ammonium ion is reacted with bydroxide ion then it is called Hofmann elimination.

any reaction proceed through electrophilic mechanism or nucleophilic mechanism is decided by looking the nature of substrate and as well as the nature of reagent. reagent means electrophile or nucleophile.

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