Bis(pinacolato)diboron, B2pin2
See also: Bis(neopentylglycolato)diboron, Tetrahydroxydiboron
Recent Literature
A Pd-catalyzed reaction of water with a diboron compound as the reductant produces clean hydrogen gas
under ambient reaction conditions. The
B2Pin2-H2O system enables a selective
hydrogenation of olefins in the presence of a palladium catalyst.
D. P. Ojha, K. Gadde, K. R. Prabhu, Org. Lett.,
2016, 18, 5062-5065.
A B2Pin2-assisted copper-catalyzed semihydrogenation of alkynes
provides various
alkenes in good to excellent yields with Z-selectivity under mild
reaction conditions. The present protocol enabled convenient synthesis of
deuterium-substituted Z-alkenes using readily available ethanol-d1 as the deuterium source.
H. Bao, B. Zhou, H. Jin, Y. Liu, J. Org. Chem., 2019, 84,
3579-3589.
Rhodium-catalyzed deoxygenations and borylations of ketones with B2pin2
provide alkenes, vinylboronates, and vinyldiboronates. These reactions offer
mild reaction conditions, a broad substrate scope, and excellent
functional-group compatibility. Mechanistic studies support that the ketones
initially undergo a Rh-catalyzed deoxygenation to give alkenes via boron enolate
intermediates.
L. Tao, X. Guo, J. Li, R. Li, Z. Lin, W. Zhao, J. Am. Chem. Soc.,
2020, 142, 18118-18127.
The combination of B2pin2 and KOtBu enables a
chemoselective, metal-free reduction of aromatic nitro compounds to the
corresponding amines in very good yields in isopropanol. The reaction tolerates
various reducible functional groups.
H. Lu, Z. Geng, J. Li, D. Zou, Y. Wu, Y. Wu, Org. Lett.,
2016, 18, 2774-2776.
A visible-light-promoted transfer hydrogenation of azobenzenes proceeds
smoothly in methanol at ambient temperature in the presence of B2pin2
through a radical pathway. The reaction reduces a broad range of azobenzenes to
the corresponding hydrazobenzenes in very good yields.
M. Song, H. Zhou, G. Wang, B. Ma, Y. Jiang, J. Yang, C. Huo, X.-C. Wang, J. Org. Chem., 2021, 86,
4804-4811.
An unprecedented nickel-catalyzed reductive borylation of enaminones provides
β-ketone boronic esters via a challenging transformation of an alkenyl C(sp2)-N
bond. While B2pin2 plays a dual role in this process,
water serves as the hydrogen source.
X. Li, Z. Chen, Y. Liu, N. Luo, W. Chen, C. Liu, F. Yu, J. Huang, J. Org. Chem., 2022, 87,
10349-10358.