Epoxide/sodium azide reaction yields a-azidohydrin

[Regis]

Aryl-substituted epoxides react with aqueous sodium azide to form a-azidohydrins, NOT B-azidohydrins.  This is according to the following journal references:

JOC, 1999, 64, 6094-6096
"Ring Opening of Epoxides with Sodium Azide in Water.  A Regioselective pH-Controlled Reaction"

JOC, 1993, 58, 2663-2669
"Acid-Catalyzed Hydrolysis of cis- and trans-Anethole Oxides:  Discrete Carbocation Intermediates and Syn/Anti Hydration Ratios"

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