Question

Q2. Show the mechanism for the following rearrangement reactions products Selected Pinacol Rearrangements 1. OH Ph C-CH2-OH Ph H + H fast Ph H slower Ph Ph Ph H 2. OH H H Ph OH Ph Ph H + Ph Ph C50% 50% Ph H heat Ph Ph Ph H rate of racemization = rate of rearrangement isotopic label C is scrambled C 3. CH3 -OH 3M HCIO4 OH CH3 cis & trans-isomers are interconverted CH3 + > 90% CH3 CH3 CH3 O < 6% 4. Ph Ph OH HO 20% H2SO4 the isomeric cyclobutanone is not observed Ph Ph Ph Ph 5. OH OH 1) H2SO4, 0°C 2) quench in KOH soln. Ph CH3 CH3 Ph -CH3 CH3 Ph CH3 cat. H2SO4 (CH3CO)20 Ph CH3 Ph Ph- = C6H5- =

          Q2. Show the mechanism for the following rearrangement reactions products
Selected Pinacol Rearrangements
1.
OH
Ph
C-CH2-OH
Ph
H
+
H
fast
Ph
H
slower
Ph
Ph
Ph
H
2.
OH H
H
Ph
OH
Ph Ph
H
+
Ph
Ph
C50%
50%
Ph
H
heat
Ph
Ph
Ph
H
rate of racemization = rate of rearrangement
isotopic label C is scrambled C
3.
CH3
-OH 3M HCIO4
OH
CH3
cis & trans-isomers
are interconverted
CH3
+
> 90%
CH3
CH3
CH3
O
< 6%
4.
Ph
Ph
OH
HO
20%
H2SO4
the isomeric
cyclobutanone
is not observed
Ph
Ph
Ph
Ph
5.
OH OH
1) H2SO4, 0°C
2) quench in
KOH soln.
Ph
CH3
CH3
Ph
-CH3
CH3
Ph CH3
cat. H2SO4
(CH3CO)20
Ph
CH3
Ph
Ph-
= C6H5-
=

q2 show the mechanism for the following rearrangement reactions products selected pinacol rearrangements 1 oh ph c ch2 oh ph h h fast ph h slower ph ph ph h 2 oh h h ph oh ph ph h ph ph c50 06588

Added by Amanda G.

Question

Please give Ace some feedback