In almost all the chemistry mechanism, one of the easiest way to memorize them is to practice them constantly, It is almost all what people do!
Wittig Reaction
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Reactants: carbonyl compounds and phosphorous ylids. Product: Alkene |
Phosophorous ylids is one of the reagent to react in wittig reaction = below is one of the examples.
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Some other ylids can also replace: CH2 group on phosophorous to CRH group. To prepare ylid above from PPh3P, we need to do one thing before! For exam purpose: What is X below? |
X is CH3 - OH ( methanol)
Stereoselectivity in the Wittig reaction depends on the ylid. Those with anion-stabilizing substituents adjacent to negative charge produce predominantly E- alkenes (thermodynamic control). Those without stabilising groups give predominantly Z- alkenes (kinetic control).
Fischer Esterifcation
Product: ester
Which step is the fischer esterfication below?
(i) Oxidative cleavage of methylindene
(ii) Fischer exterification
(iii) claisen condensation
(iv) alkylation
(v) prenyl bromide
(vi) and (vii) are isomer
(vi) prenyl ether
(vii) kapachol
Last step is the cyclization with the concentrated sulfuric acid