IIT JAM

follow

Top Resources

S

Simun Mishra posted an Question

July 01, 2020 • 13:50 pm

30 points

IIT JAM
Chemistry (CY)

Can u pls explain me how the addition of e-nu became syn and anti and how to know

1 Answer(s)

0 Likes
4 Comments
0 Shares

>
Priyanshu kumar Best Answer

see this simun...
- Likes(1)
- Reply(5)
like when Br2 like reagent are present then the addition will be anti and Hx like agent then syn
- Like(0)
yes see the condition...you understand...in presence of HX there is possibility of anti product too because rotation about single bond occurs but syn product is major
- Like(0)
got simun??
- Like(0)
ok tq so much
- Like(0)
welcome simun and pls accept the ans. too😊
- Like(0)

>
Priyanshu kumar

the picture you have send shows the stereochemistry in different cases...when the electrophilic part and nucleophilic part of the reagent is not the same and addition changes in different cases(syn & anti) the product becomes threo(opposite configuration) and erythro(same configuration) forms depending on cases
- Likes(0)
- Reply(0)

>
Priyanshu kumar

got simun?? the above figure clearly explain you when the addition become anti when it become syn
- Likes(0)
- Reply(0)

>
Priyanshu kumar

see this image
- Likes(1)
- Reply(15)
got it simun??
- Like(1)
but how to know in which case addition is syn and in which case addition is anti
- Like(0)
can u explain about syn addition
- Like(0)
yes see when the electrophilic part and nucleophilic part of reagent from same side of double bonded carbon atom as a formation of intermediate ion pair then addition is syn
- Like(0)
see above image
- Like(0)
got it??
- Like(0)
when the reagent is dipole means
- Like(0)
means there is sufficient electronegativity differenece between them so that it gets dissociates into positively and negatively part
- Like(0)
can u give me example of the 2 in any compounds
- Like(0)
example of which??
- Like(0)
any example in which syn addition occurs and in which anti addition occure
- Like(0)
like what will be the reactant and what will be the reagent condition for syn and anti addition
- Like(0)
this type of addition firstly applied to unaaturation compound..so reactant must have unsaturation other thing if the reagent have sufficiently dipole moment then ion pair is formed then syn addition occurs and at last if cyclic intermediate is formed like chloronium ion ,bromonium ion or non-classical carbocation type then anti addition occurs
- Like(0)
I m very much confused in this 😔😔
- Like(0)
okk let me send u images
- Like(0)

T