Lewis Acid Mediated Conjugate Addition of Isocyanides to β-Hydroxy-α-diazo Carbonyls: Synthesis of β-Carboxamido-α-diazo Carbonyl Compounds

Abstract

A Lewis acid mediated conjugate addition of isocyanides to β-hydroxy-α-diazo carbonyls has been developed for the first time. The reaction realizes the efficient construction of quaternary carbon centers and provides a novel and efficient strategy for the synthesis of β-carboxamido-α-diazo carbonyls that would be otherwise difficult to form in a single step. Further applications, including synthesis of methylenecyclohexane, spiro-β-lactam, and nitrogen-bridged tricyclic β-lactam, demonstrated the tremendous potential of the coupling reaction.

Visible light-induced radical cyclization of o-alkenyl aromatic isocyanides with thioethers: direct synthesis of 2-thioquinolines

“…Therefore, development of visible-light-induced 6- endo-trig radical cyclization of o -alkenyl aromatic isocyanides, especially for the radical cyclization of o -alkenyl aromatic isocyanides with thioethers, is a highly desirable, yet challenging goal. As a continuation of our studies on the applications of isocyanides 14 and visible-light-induced radical reactions, 15 herein we report a novel visible-light-induced radical cyclization of o -alkenyl aromatic isocyanides with thioethers for the first time (Scheme 1(d)). This reaction offers a new and efficient strategy for the synthesis of highly functionalized 2-thioquinolines in a single step.…”

Visible Light‐Induced [3+2] Annulation Reaction of Alkenes with Vinyl Azides: Direct Synthesis of Functionalized Pyrroles

“…Thus, development of a general and metal-free method to access pyrroles via a visiblelight-induced [3+2] annulation of vinyl azides and diverse alkenes with broad functional group tolerance is highly desirable, yet a challenging goal. As a continuation of our studies on the synthesis of nitrogen-containing compounds, [14] herein, we report a visiblelight-induced [3+2] annulation of alkenes with vinyl azides in the presence of organic dye photocatalysts without other additives. The reaction works with a broad range of polarized olefins, and provides a simple and novel method for the synthesis of polysubstituted pyrroles in a single step (Scheme 1, b).…”

“…The evaluation of solvents revealed that DCM seemed to be the best choice. Other solvents tested, such as DCE, MeCN and toluene, gave lower product yields (entries [12][13][14]. When the reaction was carried out at 40 °C under otherwise identical conditions, the product 3aa was produced in 58% yield (entry 15).…”