The reaction of a sulfamate ester derived rhodium nitrenoid species with an alkyne produces a versatile intermediate, capable of cascading into a wide variety of secondary transformations. The nature of the intermediate has been probed by reactivity studies, and the synthetic utility of the cascade process, which facilitates the construction of complex heterocyclic structures from remarkably simple acyclic precursors, is highlighted.

We have developed an automated photochemical microfluidics platform that integrates a 1 kW high-pressure Hg vapor lamp and allows for analytical pulse flow or preparative continuous flow reactions. Herein, we will discuss the use of this platform toward the discovery of new chemotypes through multidimensional reaction screening. We will highlight the ability to discretely control wavelengths with optical filters, allowing for control of reaction outcomes.

In an effort to utilize microfluidics to enable photochemistry, we have devised a method for fabrication of devices with UV-transmissive glass. The photochemical device is successfully incorporated into a system utilizing high-pressure capillary mercury lamps and cooling system. We have demonstrated the ability to carry out photochemical transformations with substantial rate acceleration. Furthermore, we highlight the ability to carry out analytical-scale reactions on a pulse flow automated system while modulating wavelength and residence time to identify optimal photochemical reaction conditions. The analytical conditions were also successfully converted to continuous-flow preparative scale.

No abstract

Synthesis of α-Aminocyclopropanes and β-Aminostyrenes. -The process leads to a wide range of heterocyclic products. It proceeds as Friedel-Crafts termination of the metallonitrene/alkyne cascade sequence for substrates bearing aromatic groups at the terminal carbon or via cyclopropanation for substrates with an olefin moiety at the end of the chain. Sulfur trioxide extrusion from the products allows formation of an pyrrole ring [cf.(XI)]. -(THORNTON, A. R.; MARTIN, V. I.; BLAKEY*, S. B.; J. Am. Chem. Soc. 131 (2009) 7, 2434-2435; Dep. Chem., Emory Univ., Atlanta, GA 30322, USA; Eng.) -Y. Steudel 28-150