A Radical Procedure for the Anti-Markovnikov Hydroazidation of Alkenes

Abstract

A one-pot procedure for the efficient hydroazidation of alkenes involving hydroboration with catecholborane followed by reaction with benzenesulfonyl azide in the presence of a radical initiator is described. The regioselectivity is controlled by the hydroboration step and corresponds in most cases to an anti-Markovnikov regioselectivity. This procedure is applicable to a wide range of alkenes and gives excellent results with 1,2-disubstituted and trisubstituted alkenes.

Functionalization of Styrenes by Copper‐Catalyzed Borylation/ ortho‐Cyanation and Silver‐Catalyzed Annulation Processes

“…On the basis of the Li precedent, we propose that Ag III -mediated oxidation of the alkyl(Bpin) species 2 generates the homobenzylic radical 24, [12] which undergoes cyclization onto the nitrile to afford the nitrogen-centered radical 25 (Scheme 2). [15] Thea dvances described here,i nvolving the cyclization of alkylBPin derivatives with nitriles,thus provide an important complement to previously developed radical cyclization processes involving alkylborane precursors. [15] Thea dvances described here,i nvolving the cyclization of alkylBPin derivatives with nitriles,thus provide an important complement to previously developed radical cyclization processes involving alkylborane precursors.…”

Enantioselective Hydroazidation of Trisubstituted Non‐Activated Alkenes

“…[2] Owing to the rich chemistry of organic azides, [3] the hydroazidation reaction represents ap articularly attractive process.T he addition of hydrazoic acid and its derivatives (TMSN 3 and NaN 3 )t on on-activated olefins is difficult and limited to substrates forming stable tertiary and benzylic carbocations. [6] This reaction provided the corresponding products with excellent anti-Markovnikov regioselectivity (Scheme 1). [5] Recently,w ed escribed ar adical procedure for the hydroazidation of alkenes using catecholborane as the hydroboration agent followed by reaction with benzenesulfonyl azide as ar adical trap.…”

4.05 Addition of HX Reagents to Alkenes, Alkynes, and Allenes without Transition Metal

“…93 This procedure is applicable to a wide range of alkenes and gives excellent results with mono-, di-, and trisubstituted alkenes (equation 130). β-Citronellene underwent 6-exo-trig cyclization to afford the corresponding organic azide at a high concentration of benzenesulfonyl azide (equation 131).…”