The intermolecular C-H trifluoromethoxylation of arenes remains a long-standing and unsolved problem in organic synthesis. Herein, we report the first catalytic protocol employing a novel trifluoromethoxylating reagent and redox-active catalysts for the direct (hetero)aryl C-H trifluoromethoxylation. Our approach is operationally simple, proceeds at room temperature, uses easy-to-handle reagents, requires only 0.03 mol % of redox-active catalysts, does not need specialized reaction apparatus, and tolerates a wide variety of functional groups and complex structures such as sugars and natural product derivatives. Importantly, both ground-state and photoexcited redox-active catalysts are effective. Detailed computational and experimental studies suggest a unique reaction pathway where photoexcitation of the trifluoromethoxylating reagent releases the OCF radical that is trapped by (hetero)arenes. The resulting cyclohexadienyl radicals are oxidized by redox-active catalysts and deprotonated to form the desired products of trifluoromethoxylation.

The objective of this paper was to identify oral bioavailability enhancing approaches for a poorly water-soluble research compound during drug discovery stages using minimal amounts of material. LCQ789 is a pBCS (preclinical BCS) Class II compound with extremely low aqueous solubility (<1 µg/mL) and high permeability, therefore, resulting in very low oral bioavailability in preclinical species (rats and dogs). A number of solubility and/or dissolution enhancing approaches including particle size reduction, solid dispersions, lipid-based formulations and co-crystals, were considered in order to improve the compound's oral bioavailability. High-Throughput Screening (HTS) and in silico modeling (GastroPlus™) were utilized to minimize the compound consumption in early discovery stages. In vivo evaluation of selected physical form and formulation strategies was performed in rats and dogs. Amongst the formulation strategies, optimized solid dispersion and lipid-based formulation provided significant improvement in drug dissolution rate and hence, oral bioavailability. In addition, a significant impact of physical form on oral bioavailability of LCQ789 was observed. In conclusion, a thorough understanding of not only the formulation technique but also the physical form of research compounds is critical to ensure physical stability, successful pharmacokinetic (PK) profiling and early developability risk assessment.

The trifluoromethoxy (OCF3) radical is of great importance in organic chemistry. Yet, catalytic and selective generation of this radical at room temperature and pressure remains a longstanding challenge. Herein, we report the design and development of a redox- active cationic reagent 1 that enables the formation of the OCF3 radical in a controllable, selective, and catalytic fashion under visible light photocatalytic conditions. More importantly, the reagent allows catalytic, intermolecular C-H trifluoromethoxylation of a broad array of (hetero)arenes and biorelevant compounds. Experimental and computational studies suggest single electron transfer (SET) from excited photoredox catalysts to 1 resulting in exclusive liberation of the OCF3 radical. Addition of this radical to (hetero)arenes gives trifluoromethoxylated cyclohexadienyl radicals that are oxidized and deprotonated to afford the products of trifluoromethoxylation.

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The intermolecular C−H trifluoromethoxylation of arenes remains a long‐standing and unsolved problem in organic synthesis. Herein, we report the first catalytic protocol employing a novel trifluoromethoxylating reagent and redox‐active catalysts for the direct (hetero)aryl C−H trifluoromethoxylation. Our approach is operationally simple, proceeds at room temperature, uses easy‐to‐handle reagents, requires only 0.03 mol % of redox‐active catalysts, does not need specialized reaction apparatus, and tolerates a wide variety of functional groups and complex structures such as sugars and natural product derivatives. Importantly, both ground‐state and photoexcited redox‐active catalysts are effective. Detailed computational and experimental studies suggest a unique reaction pathway where photoexcitation of the trifluoromethoxylating reagent releases the OCF3 radical that is trapped by (hetero)arenes. The resulting cyclohexadienyl radicals are oxidized by redox‐active catalysts and deprotonated to form the desired products of trifluoromethoxylation.