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We report herein an ortho‐C–H alkenylation reaction of aryl imines with alkenyl phosphates promoted by a cobalt–N‐heterocyclic carbene (NHC) catalytic system. While commercially available bulky NHC ligands exhibited only modest catalytic activity, elaboration of the nitrogen substituents and backbone of the NHC enabled the desired transformation to proceed in high yield at a mild temperature. The new Co–NHC system proved applicable to a variety of aryl imines and alkenyl phosphates to afford ortho‐alkenylated aryl imines, which serve as precursors to benzofulvene derivatives. MOE (Min. of Education, S’pore) Accepted version

A cobalt–chiral phosphoramidite catalyst promotes enantioselective imine-directed C2-alkylation of Boc-protected indoles with styrenes. The reaction affords 1,1-diarylethane products in moderate to good yields with good enantioselectivities under mild conditions. A deuterium-labeling experiment suggests that the enantioselectivity is controlled by both the styrene insertion and the C–C reductive elimination steps. Accepted version

A cobalt–chiral phosphoramidite catalyst promotes enantioselective imine-directed C2-alkylation of Boc-protected indoles with styrenes. The reaction affords 1,1-diarylethane products in moderate to good yields with good enantioselectivities under mild conditions. A deuterium-labeling experiment suggests that the enantioselectivity is controlled by both the styrene insertion and the C–C reductive elimination steps.

An improved cobalt-based catalytic system has been developed for the branched-selective addition of aromatic ketimines to styrenes. With an appropriate combination of triarylphosphine and the Grignard reagent, the reaction takes place smoothly at room temperature to afford 1,1-diarylethane derivatives with high regioselectivity.

An improved cobalt-based catalytic system has been developed for the branched-selective addition of aromatic ketimines to styrenes. With an appropriate combination of triarylphosphine and the Grign...

The Co(II)/imidazolium catalyst in combination with neopentylmagnesium bromide allows arylation at room temperature.

A quaternary catalytic cobalt system promotes the hydroarylation of internal alkynes with aromatic imines through chelation-assisted C—H bond cleavage.

An ortho-arylation reaction of aromatic imines with aryl chlorides has been achieved using a cobalt–N-heterocyclic carbene catalyst in combination with a neopentyl Grignard reagent. The reaction takes place at room temperature to afford biaryl products in moderate to good yields.

Chelation-controlled addition of arylpyridines or aromatic imines towards internal alkynes proceeds readily in the presence of a CoBr2—monophosphine catalyst to give tri-substituted olefins with high regio- and stereoselectivities in most cases.

Information transparency is a popular topic in capital markets. A firms corporate governance policy, which influences its disclosure behavior and disclosure quality, influences the information transparency perceived in relation to that firm. It was previously understood that greater information asymmetry between investors and issuers/underwriters translates into a larger discount required to be offered in bond pricing by the issuing firm, to attract investors. In this paper, we numerically analyze: (a) the effect of the composition of the board structure on corporate information transparency under the code law system, and (b) the effect of information transparency on the initial return rate of convertible bonds. The results of our study revealed that the board structure affects corporate information disclosure policies under the code law system. Specifically, CEO duality tends to bring about lower information transparency, whereas better information transparency emanates from a higher proportion of independent directors. However, there is a lack of conclusive evidence to support the view that the shareholdings of directors and large shareholders are correlated with information transparency. We also show numerically that greater information transparency combined with lesser information asymmetry (between insiders and outsiders) leads to a lower initial return rate of convertible bonds.