Enantioselective dioxytosylation of styrenes using lactate-based chiral hypervalent iodine(III)
نویسندگان
چکیده
A series of optically active hypervalent iodine(III) reagents prepared from the corresponding (R)-2-(2-iodophenoxy)propanoate derivative was employed for the asymmetric dioxytosylation of styrene and its derivatives. The electrophilic addition of the hypervalent iodine(III) compound toward styrene proceeded with high enantioface selectivity to give 1-aryl-1,2-di(tosyloxy)ethane with an enantiomeric excess of 70-96% of the (S)-isomer.
منابع مشابه
Enantioselective Prévost and Woodward reactions using chiral hypervalent iodine(III): switchover of stereochemical course of an optically active 1,3-dioxolan-2-yl cation.
Optically active 1,3-dioxolan-2-yl cation intermediates were generated during enantioselective dioxyacetylation of alkene with chiral hypervalent iodine(III). Regioselective attack of a nucleophile toward the intermediate resulted in reversal of enantioselectivity of the dioxyacetylation.
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