Cobalt-Catalyzed Cross-Coupling Reactions of Heterocyclic Chlorides with Arylmagnesium Halides and of Polyfunctionalized Arylcopper Reagents with Aryl Bromides, Chlorides, Fluorides and Tosylates
A range of aromatic organocopper or organomagnesium compounds undergo smooth cross-coupling reactions with aryl bromides, chlorides, fluorides and tosylates, leading to polyfunctionalized aromatics or heterocycles in the presence of cobalt salts (5-7.5 mol%) as catalysts. Very mild reaction conditions are needed and, in the case of cross-coupling with organocopper compounds, Bu4NI (1 equiv) and 4-fluorostyrene (20 mol%) are essential as promoters for successful couplings.
Method of preparing an optical connector and optical devices comprising the optical connector prepared thereby
申请人:Dow Corning Corporation
公开号:US10551566B2
公开(公告)日:2020-02-04
A method of preparing an optical connector located within a gap between a first optical assembly and a second optical assembly is provided. The optical connector includes a contrast layer having at least one cured bridge portion and at least one uncured portion formed from a first composition having a first refractive index (RI1). The method comprises applying a second composition having a second refractive index (RI2) on the contrast layer to form a second layer and mixing at least a portion of the second layer with the at least one uncured portion of the contrast layer to form at least one intermixed portion having a third refractive index (RI3), wherein R|1>R|3>RI2, and then curing the intermixed portion and optional second layer such that each one of the at least one cured bridge portions is surrounded by an intermixed portion and optional second layer.