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Light-driven silane functionalization using disulfide and dichloromethane

2026-04-15T08:10:35Z

Title: Light-driven silane functionalization using disulfide and dichloromethane Author(s): Lee, Jiin; Kim, Hyunji; Lee, Sunggi Abstract: Organosilicon compounds are of great importance in material and synthetic chemistry. Herein, we disclose a practical and general silane functionalization protocol that enables direct access to silanols and silyl ethers. The process features mild, environmentally benign conditions and enables the transformation of diverse silanes into valuable organosilicon compounds.

Cyclopropanation of Alkenes with Dichloromethane and Chloroform via Halogen Atom Transfer Using Amine Carboxyborane

2026-02-10T09:10:20Z

Title: Cyclopropanation of Alkenes with Dichloromethane and Chloroform via Halogen Atom Transfer Using Amine Carboxyborane Author(s): Park, Changhee; Lee, Sunggi Abstract: Cyclopropanes are privileged motifs in medicinal chemistry due to their role as bioisosteres of arenes, alkenes, and small alkyl groups. Herein, we report a transition-metal-free, photoredox-catalyzed cyclopropanation of diverse alkenes via halogen atom transfer between dichloromethane (CH2Cl2) as a C1 synthon and amine-ligated boryl radicals generated from amine carboxyborane. This method proceeds under mild reaction conditions, exhibits a broad substrate scope, and is scalable. The synthetic utility is further highlighted by deuterium incorporation using CD2Cl2 and the formation of chlorocyclopropane products using chloroform (CHCl3) and CDCl3, enabling access to valuable chlorinated and isotopically labeled cyclopropanes.

Real-Time Visualisation of Reaction Kinetics and Dynamics: Single-Molecule Insights into the Iminium-Catalysed Diels-Alder Reaction

2025-12-18T02:40:54Z

Title: Real-Time Visualisation of Reaction Kinetics and Dynamics: Single-Molecule Insights into the Iminium-Catalysed Diels-Alder Reaction Author(s): Park, Minsoo; Ahn, Yongdeok; Cho, Juhyeong; Jang, Juhee; Lee, Wonhee John; Seo, Sangwon; Lee, Sunggi; Seo, Daeha Abstract: Investigation of the fundamental microscopic processes occurring in organic reactions is essential for optimising both organocatalysts and synthetic strategies. In this study, single-molecule fluorescence microscopy was employed to study the Diels-Alder reaction catalysed by a first-generation MacMillan catalyst, providing direct insights into its kinetic dynamics. This reaction proceeds via a series of reversible processes under equilibrium conditions (S -><- IM1 -><- IM2 -> P, IM1 and IM2: N,O-acetal and iminium ion intermediates, respectively). The individual reaction trajectories of single molecules were directly observed in real-time, and the kinetic transitions between the different states were quantitatively analysed using a hidden Markov model, thereby enabling precise determination of the kinetic rate constants and transition probabilities at the single-molecule level. In particular, the unique structural features of the MacMillan catalyst were probed to reveal how specific interactions stabilise the reaction intermediates and influence their kinetic behaviours. These findings highlight the importance of single-molecule fluorescence microscopy in understanding the fundamental mechanisms of organic reactions and guiding the rational design of more effective catalysts.

The Giese reaction of alkyl bromides using amine carboxyboranes

2025-07-25T02:43:22Z

Title: The Giese reaction of alkyl bromides using amine carboxyboranes Author(s): Park, Changhee; Gi, Seyun; Yoon, Seongkyeong; Kwon, Seong Jung; Lee, Sunggi Abstract: Amine carboxyborane enabled efficient halogen atom transfer (XAT) with 1 degrees, 2 degrees, and 3 degrees alkyl bromides, resulting in Giese addition products with various electron-deficient double bonds. Moreover, direct addition of several boryl radicals was also possible using several ligated carboxyboranes.