Accelerated Hantzsch electrospray synthesis with temporal control of reaction intermediates

Accelerated Hantzsch electrospray synthesis with temporal control of reaction intermediates.

Complex chemical reactions can occur in electrosprayed droplets on the millisecond time scale. The Hantzsch synthesis of 1,4-dihydropyridines was studied in this way using on-line mass spectral analysis to optimize conditions and characterize the product mixture. Changing the distance between the nanospray source and the MS inlet allowed exploration of reaction progress as a function of droplet...

Sulfated Titania Nanoparticles: an Efficient Catalyst for the Synthesis of Polyhydroquinoline Derivatives through Hantzsch Multicomponent Reaction

Sulfated titania nanoparticles (SO42-/TiO2 NPs) were synthesized using titanium tetraisopropoxide (TTIP) by the sol-gel method. The structure and morphology of the prepared nanocatalyst was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and Brunauer–Emmett–Teller (BET) methods as well as Fourier transform infrared (FT-IR) and energy dispersive X-ray (EDX) spectr...

Two New Devices for Identifying Electrochemical Reaction Intermediates with Desorption Electrospray Ionization Mass Spectrometry.

Desorption electrospray ionization mass spectrometry (DESI-MS) previously has been used to capture and identify transient intermediates in electrochemical redox reactions on a platinum-covered rotating waterwheel. We present here two different setups that use a flat surface with porous carbon tape as the working electrode, where analyte-containing microdroplets from the DESI probe contacted wit...

Accelerated Hantzsch electrospray synthesis with temporal control of reaction intermediates† †Electronic supplementary information (ESI) available: Spectra for all on-line, off-line, and substituent studies as well as photographs of experimental setups are supplied. See DOI: 10.1039/c4sc02436b Click here for additional data file.

Enantioselective organocatalytic Hantzsch synthesis of polyhydroquinolines.

The four-component Hantzsch reaction provides access to pharmaceutically important dihydropyridines. To expand the utility of this method, we have developed a route under organocatalytic conditions with good yields and excellent ee's. Through catalyst screening, we found that a BINOL-phosphoric acid allowed enantioselective synthesis of six-membered heterocycles with a variety of substitution p...