Chelation-Assisted Catalytic C-C, C-Si, and C-Halogen Bond Formation by Substitution via the Cleavage of C(sp²)-H and C(sp³)-H Bonds

Abstract

Catalytic, regioselective C H functionalizations have been extensively studied over the past two decades. In this account, we report our results on catalytic C C, C Si, and C halogen bond formation reactions by substitution via the cleavage of C H bonds. Catalytic arylation with arylboronates was developed and applied to the convenient synthesis of polycyclic aromatic hydrocarbons. Alkenylation reactions were also realized by the use of alkenylboronates and alkenyl esters. Various carbonyl containing substituents were introduced using carbamoyl chlorides, alkyl chloroformates, acyl chlorides, and cyclic alkenyl carbonates. C Si bonds were formed by reactions with hydrosilanes and vinylsilanes. C H halogenation reactions were achieved by a combination of C H bond cleavage and electrochemical oxidation and were applied to one pot arylation reactions using the Suzuki Miyaura coupling prodecure.

Development of Step‐Saving Alternative Synthetic Pathways for Functional π‐Conjugated Materials

“…[1] Further, in order to improve reaction efficiencies and meet some of the conditions rquired in green chemistry, scientists have been working hard since almost three decades to discover more effective synthetic methodologies with high atom-/step-economy and to minimise hazardous wastes, using the pronounced direct CÀ H bond functionalizations. Pioneers such as Murai, [2][3][4][5][6][7] Chatani, [8][9][10] Kakiuchi, [11][12][13] Mori, [14] Fagnou, [15] Sanford, [16] Ackermann, [17] Yorimitsu, [18] Itami, [19] and Yu [20] et al However, we noticed that, in most cases, synthetic chemists focused on creating new catalytic systems with improved efficiencies, enhancing reaction selectivity, or challenging on difficult chemical transformations. Nevertheless, the potential function and application of the created methodologies and products were much less explored, particularly the application associated with organic semiconducting materials.…”

Rotational Behavior about the N3–Pyridyl Bond in 3-(Pyridin-2-yl)quinazolin-4-one and 4-Thione Derivatives

“…Since the 2-pyridyl group has also been widely used as a directing group for C–H activation in the field of synthetic organic chemistry, we were curious about the rotational behavior around the N3–(2-pyridyl) bond. In this Note, we report the rotational barriers and pathways of the N3–(2-pyridyl) bond in 2- iso -propyl-3-(pyridin-2-yl)­quinazolin-4-one and 4-thione derivatives.…”