In friedel-crafts alkylation of benzene with an alkyl halide and
AlCl3:
1. In terms of intermediate and product stabilities explain why
the ortho and para isomers would be favored under kinetic
conditions and why the meta isomer would be favored under
thermodyanmic conditions?
2. What function does the nitromethane serve in the kinetic
reaction?
3. What reactants would you employ for the preparation of the
following compounds by reactions of the Friedel-crafts type?
- a. diphenylmethane
- b. 4-bromophenyl phenyl...
1. Friedel craft alkyation such as methylation of Nitro benzene did
not yield any either meta or ortho and para products; essentially
no reaction occurred. However alkylation of phenol (hydroxybenzene
) gave ortho and para methylphenol. Explain
2. Bromination of aniline gives both ortho and para
substituted bromo aniline respectively. However, the nitration of
the same aniline gives only a meta-nitroaniline upon nitration.
Discuss why.
Wittig Reaction:
Under what conditions does the Wittig reaction favor the cis
isomer? Under what conditions does the Wittig reaction
favor the trans isomer?
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What is the effect of changing the following factors in a
nucleophilic substitution reaction of alkyl halides: nature of the
halide, nature of the solvent, relative concentrations of the
reactants, temperature of the reaction, and nature of the
nucleophile?
question 1
The Friedel-Crafts reaction to form BHA forms both isomers
equally while the BHT
synthesis only forms on regioisomer (where the t-Bu are ortho to
the alcohol). Why is the
selectivity for one regioisomer so much higher in the reaction
to form BHT?
1. what effect does a catalyst have on the reaction rate?
explain
2. predict how the reaction rate would change if the
concebtration of the sodium meta-bisulfite soltion were changed
insted of the potassium iodate concentration.
Vitride has the formula NaAlH2(OCH2CH2OCH3)2. it can be added to alkyl bromide / magnesium solutions to start a gringnard reaction. however it is a hydride source and is capable of adding to the c=o bonds in addition to reacting with water.
these questions pertain to an organic lab I did. we prepared an gringnard reaction of 0.05g (0.021 moles) Mg with 2.5mL (0.023 mol) of 1-bromobutane and 1.8mL(0.0197 moles) of 2-methylpropanal as the electrophilie.
1) As a preventative measure,...