An anthranilamide-substituted borane [H–B(aam)]: its stability and application to iridium-catalyzed stereoselective hydroboration of alkynes

Abstract

A robust borane [H–B(aam)] was synthesized and used for Ir-catalyzed stereoselective hydroboration of terminal alkynes.

Synthetic Chemistry with Lewis Acidity‐Diminished B(aam) and B(dan) Groups: Borylation Reactions and Direct Cross‐Couplings

“…Yoshida also developed an aam‐substituted borane, H−B(aam), as a B(aam)‐installing reagent, which was readily accessible by dehydrogenative coupling of BH 3 ⋅ SMe 2 with aam‐H 2 in excellent yield (Scheme 6). [11] H−B(aam) was found to be enough stable to air and moisture, being in stark contrast to usual Lewis acidic boranes, and thus can be used as a stable, easy‐to‐handle substitute for H−B(pin).…”

“…Direct B(aam)‐installing reaction into terminal alkynes with H−B(aam) under iridium catalysis was achieved via hydroboration in 2019, leading to the stereoselective formation of diverse linear ( E )‐alkenyl–B(aam)s, was reported (Scheme 9). [11] A boryliridium hydride complex arising from oxidative addition of H−B(aam) to the Ir catalyst could be isolated and characterized by NMR studies, and should be involved in the catalytic cycle.…”

“…Synthetic utilization of the direct SMC was demonstrated by the formal total synthesis of a pharmaceutically important palovarotene using an ( E )‐alkenyl–B(aam), being prepared through the above iridium‐catalyzed hydroboration with H−B(aam) (Scheme 11). [11] …”

An Efficient Ni/Pd Catalyzed Chemoselective Synthesis of 1,3,2‐Benzodiazaborininones from Boronic Acids and Anthranilamides

“…[8] The B(aam) moieties also serve as directing groups for catalytic ortho-C(aryl)À H silylation. [10] Conventional methods involve the construction of 1,3,2-benzodiazaborininones based on the condensation of boronic acid with commercially available anthranilamide in toluene under reflux. [10] Conventional methods involve the construction of 1,3,2-benzodiazaborininones based on the condensation of boronic acid with commercially available anthranilamide in toluene under reflux.…”

“…[9] They have been applied to iridium-catalyzed stereoselective hydroboration of alkynes. [10] Conventional methods involve the construction of 1,3,2-benzodiazaborininones based on the condensation of boronic acid with commercially available anthranilamide in toluene under reflux. [11] This method requires high temperature and the yield is not ideal.…”