1yes srinath ... dats my doubt as well.... :)
32 Answers
1pata nahi kaise upar wala carbon pe attack hoga aur kyun hoga [12] ....
11Bas Yaar bahut huaa mere dimaag ne iss topic par sochnaa band kar diya ab.........
Lagta book kholni hi padegi.......
1IN ANS D MECHANISM PROPOSED IS SAME AS SKY BUT IN 1ST STEP ATTACK ON D UPPER WALA CARBON
1no yaar... betain intermediate forms because : P=O bond is srtonger than P=CH2.
11@sky.
Here the compound is not having carbonyl group.
My 3rd step structure is somewhat similar to BETAIN INTERMEDIATE.
1there is BETAIN INTERMEDIATE in the mechanism ...
here no such thing is there...
11well if u go according to wittig's rxn mechanism, P shud attack but i don't know clearly about this..........
1@ sunil acc to me due to double bond in conjugation where u have shown c- in 1st step it would be c+ n attack must be done by c of c-pph3
11iskaa matlab khaaali peeeli dimaag par itna zor dala maine aur ye banaya.....
Richa pls check the question.
1and i thnk... the reactant shud have =O in place of =CH2 .
richa plz chcek...
1no dhruv ,,, e-density is not high on P ...
i did that coz PPh3 is a good leaving group...
1i think sky is right..most prob due to high e- density on P, CH2 attacks on C and not P..
11richa i think this might be the mechanism.
I'm not quite sure........
11Sky, I've problem in ur 2nd step.... Shouldn't the -ve charge on CH2 Should attack on +vely charged P....
In my 4th step, actually due to more crowd there the bond bwtween Ph3P and CH2 breaks and the resulant product is formed.............
1i have doubt wid your 4th step sunil...
i basically cudn understant wat happened there...
1but is this wittig reaction?? [7] [7] [12]
in wittig there's =O in the reactant ...
and last which forms Ph3P=0 .
11mehnat kahan nahi lagti....... Likhne me bhi mehnat lagti hai.........
yaar scanner hai nahi aur mobile ka camera vga hai, isliye banana hi padta hai paint par.........
33lag to raha hai...
it was asked to give mech for the product and u are getting product... :)
so correct to me.. :)
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