Metal‐Free Nitrile Diboration through Activation by an Electron‐Rich Diborane

Abstract

Diboration of unsaturated organic compounds is an extremely useful reaction in synthetic chemistry. Herein, we report the first diboration of a nitrile by an electron-rich diborane, mediated by an electrophilic borane. The reaction is metal-free, and all of the reagents are readily available.

Catalyst‐Free Hydroboration of CO2 With a Nucleophilic Diborane(4)

“…Herein, we report the first catalyst‐free hydroboration of CO 2 with a neutral boron compound, the nucleophilic sp 3 ‐sp 3 hybridized diborane [HB(hpp)] 2 (hpp=1,3,4,6,7,8‐hexahydro‐2 H ‐pyrimido[1,2‐a]pyrimidinate), 1 . Our results pave the way for the use of nucleophilic diboranes in hydroboration reactions, especially for the catalyst‐free hydroboration of electron‐poor substrates.…”

“…[16] Herein, we report the first catalyst-free hydroboration of CO 2 with an eutral boron compound, the nucleophilic sp 3 -sp 3 hybridized diborane[ HB(hpp)] 2 (hpp = 1,3,4,6,7,8-hexahydro-2Hpyrimido[1,2-a]pyrimidinate), 1. [17][18][19] Our results pave the way for the use of nucleophilic diboranes in hydroboration Scheme1.a) Hydroboration of CO 2 with electrophilicH B 9BBN ,c atalyzed by PtBu 3 (Stephan et al). [8] b) Catalytic reaction of CO 2 with an electrophilic diborane( Sadighi et al).…”

The Borole Route to Reactive Pentafluorophenyl‐Substituted Diboranes(4)

“…[17] Marder et al have described ar are example of metal-catalyzed 1,1-diboration of an alkenyl borane substrate. [18] Our example of the formation of the geminal bisboryl compound 14 by treatment of the tetraaryldiborane(4) 6b with the terminal acetylene 1-pentyne is special. Ther eaction occurs in metal-free conditions.T he thermally induced reaction is …”

Nucleophilic Neutral Diborane(4) Compounds with sp3–sp3‐Hybridized Boron Atoms

“…The high nucleophilicity of [HB(hpp)] 2 can be used for diboration reactions that are not feasible with the traditionally employed electrophilic diboranes such as B 2 (cat) 2 . An example is the diboration of nitriles . The nitrile is activated by the addition of (Me 2 N) 2 BBr/KPF 6 .…”