Q9(b)(ii). Sharpless asymmetric epoxidation of an allylic alcohol
Predict the major product formed with correct stereochemistry in the reaction given below. What is the role of t-butyl hydroperoxide and titanium tetraisopropoxide in the given reaction? [allylic alcohol given in the paper; t-BuOOH, Ti(O-i-Pr)₄, L-(+)-diethyl tartrate, CH₂Cl₂, −78 °C → ?]
Answer in brief
(2S,3S)-2,3-Epoxy-3-methylhexan-1-ol. t-BuOOH is the oxidant (oxygen source); Ti(O-i-Pr)₄ is the Lewis-acid catalyst that holds tartrate, alcohol and peroxide together.
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CoversSharpless epoxidationasymmetric epoxidationdiethyl tartratetitanium isopropoxideallylic alcoholTBHP
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