Concept of Ir-catalyzed C H bond activation/borylation by noncovalent interaction

Amide Effects in C−H Activation: Noncovalent Interactions with L‐Shaped Ligand for meta Borylation of Aromatic Amides

“…It has been demonstrated that while esters gave para borylations,a mides lead to meta borylations.F or achieving high meta selectivity,a nL -shaped bifunctional ligand has been employed and engages in an O···K noncovalent interaction with the oxygen atom of the moderately distorted amide carbonyl group.This interaction provides exceptional control for meta C À Ha ctivation/borylation.Todatenoncovalentinteractions [1] have attracted substantial interest in different fields of chemistry.Several experimental investigations showed that these interactions can be similar in strength to hydrogen bonding.A sar esult, it is highly anticipated that these interactions will be introduced to catalysis.M oreover,b ased on the advancement of hydrogen bonds in transition-metal catalysis,itcould be envisaged that other types of noncovalent interactions could also play significant roles for the development of future catalytic concepts in C À Hbond activation/functionalization chemistry. Thus,i tw ould be highly desirable to integrate these two parameters,t hat is,n oncovalent interactions and transitionmetal catalyst, for the possible development of new concepts and hypotheses in CÀHa ctivation chemistry, [2] and would enable discovery of smart technologies in organic synthesis.While many C À Hb ond functionalizations [3] are now accessible,C À Hb ond borylation has potential because of the versatile synthetic transformations [4] of B À Cb onds. However,amajor challenge in CÀHb orylation of arenes is the site selectivity,w hich is largely governed by steric effects.…”

“…Todatenoncovalentinteractions [1] have attracted substantial interest in different fields of chemistry.Several experimental investigations showed that these interactions can be similar in strength to hydrogen bonding.A sar esult, it is highly anticipated that these interactions will be introduced to catalysis.M oreover,b ased on the advancement of hydrogen bonds in transition-metal catalysis,itcould be envisaged that other types of noncovalent interactions could also play significant roles for the development of future catalytic concepts in C À Hbond activation/functionalization chemistry. Thus,i tw ould be highly desirable to integrate these two parameters,t hat is,n oncovalent interactions and transitionmetal catalyst, for the possible development of new concepts and hypotheses in CÀHa ctivation chemistry, [2] and would enable discovery of smart technologies in organic synthesis.…”

One-Pot Iridium Catalyzed C–H Borylation/Sonogashira Cross-Coupling: Access to Borylated Aryl Alkynes

“…This resulted in full conversion of substrate in 10 h and the resulting borylated aromatic alkyne was isolated in 75% yield (Scheme 4). We used this protocol with a couple of other aryl borylated bromides (10,11) and the Sonogashira products were obtained in good yields (13,14). Synthesis of 14 was run in a bigger scale (10 g, 31.5 mmol) which shows the robustness of this reaction.…”

“…The regiochemistry of iridium-catalyzed CHB of arenes is traditionally governed by sterics [3,7,8]; often complementing regiochemical outcomes of electrophilic aromatic substitution and directed ortho metalation. Since its discovery [9], methods to expand regiocontrol (ortho, meta, and para) [10][11][12], sp 3 borylation protocols [13][14][15][16][17][18][19][20][21] and one-pot reactions [22][23][24][25][26][27] have been developed.…”

“…Molecules 2020, 25, 1754 9 of 13 1 H-NMR (CDCl 3 , 500 MHz): δ 8.07 (dd, J = 1.7, 1.1 Hz, 1 H), 7.98 (dd, J = 1.7, 1.1 Hz, 1 H), 7.77 (t, J = 1.7 Hz, 1 H), 1.34 (br s, 12 H, 4 CH 3 of Bpin), 0.24 (s, 9 H, 3 CH 3 of TMS); 13 C-NMR { 1 bromobenzotrifluoride (279 μL, 4 HBpin (436 μL, 384 mg, 3.00 mm out with phenyl acetylene (242 chromatography (pentane:dichlo desired product as orange yellow 1 H NMR (CDCl3, 300 MHz): H), 7.42-7.30 (m, 3 H), 1.37 (s, 12 131.8 (2 CH), 130.8 (q, 3 JC-F = 3.8 H (CH), 128.5 (2 CH), 124.1 (q, 1 JC-F (4 CH3 of Bpin); 11 3-(Trimethylsilylethynyl)-5- (4,4,5,5 From Sonogashira coupling the borylated version of 3-bromot (156 μL, 108 mg, 1.10 mmol, 1.1 (pentane/ether 9:1, Rf 0.8) furnish…”