The Experts below are selected from a list of 6 Experts worldwide ranked by ideXlab platform

Richard N. Zare - One of the best experts on this subject based on the ideXlab platform.

  • Influence of Inlet Capillary Temperature on the Microdroplet Chemistry Studied by Mass Spectrometry
    Journal of Physical Chemistry A, 2019
    Co-Authors: Shibdas Banerjee, Richard N. Zare
    Abstract:

    Often, studies of microdroplet chemistry using electrospray ionization mass spectrometry (MS) either find a negligible effect of the heated inlet capillary of the mass spectrometer on the reaction rate or do not consider its effect. In this context, we studied two reactions in microdroplets, the Pomeranz–Fritsch Synthesis of isoquinoline and the Combes quinoline Synthesis. The reagents were electrosprayed with methanol and aqueous solutions forming small and large microdroplets at flow rates of 1 and 20 μL/min, respectively. We also varied the inlet capillary temperature from 100 to 350 °C. Contrary to the view that the inlet temperature has little to no influence on the reaction rate, we found that the Pomeranz–Fritsch reaction was markedly accelerated for both solvents and for both droplet sizes on increasing the temperature, whereas the Combes Synthesis showed the opposite behavior. We propose that these strikingly different behaviors result from a competition of two effects, the evaporative cooling ve...

Shibdas Banerjee - One of the best experts on this subject based on the ideXlab platform.

  • Influence of Inlet Capillary Temperature on the Microdroplet Chemistry Studied by Mass Spectrometry
    Journal of Physical Chemistry A, 2019
    Co-Authors: Shibdas Banerjee, Richard N. Zare
    Abstract:

    Often, studies of microdroplet chemistry using electrospray ionization mass spectrometry (MS) either find a negligible effect of the heated inlet capillary of the mass spectrometer on the reaction rate or do not consider its effect. In this context, we studied two reactions in microdroplets, the Pomeranz–Fritsch Synthesis of isoquinoline and the Combes quinoline Synthesis. The reagents were electrosprayed with methanol and aqueous solutions forming small and large microdroplets at flow rates of 1 and 20 μL/min, respectively. We also varied the inlet capillary temperature from 100 to 350 °C. Contrary to the view that the inlet temperature has little to no influence on the reaction rate, we found that the Pomeranz–Fritsch reaction was markedly accelerated for both solvents and for both droplet sizes on increasing the temperature, whereas the Combes Synthesis showed the opposite behavior. We propose that these strikingly different behaviors result from a competition of two effects, the evaporative cooling ve...

Shane M. Devine - One of the best experts on this subject based on the ideXlab platform.

  • Novel annulated products from aminonaphthyridinones
    Tetrahedron, 2006
    Co-Authors: Leslie W. Deady, Shane M. Devine
    Abstract:

    Abstract 2-(4-Methoxyphenyl)-1-oxo-1,2-dihydro-1,6-naphthyridine-4-carboxamide ( 4c ) underwent Hofmann rearrangement with iodobenzene diacetate in methanol to give the corresponding 4-amino compound ( 6c ). This, when reacted with 2,4-pentanedione and then hot phosphoryl chloride (attempted Combes Synthesis) gave a new heterocyclic system, 6-(4-methoxyphenyl)-2-methylpyrido[3,2- c ]pyrrolo[2,3- e ]azocin-7(6 H )-one ( 9c ). This showed typical pyrrole-type reactivity at the 3-position. Alternatively, an attempt to convert the 4-NH 2 in 6c to 4-OH by diazotization gave, instead, a [1,2,3]triazolo[1,5- a ]pyridine-3-carboxaldehyde ( 16c ). The same series of reactions on a benzo analog, 2-methyl-1-oxo-1,2-dihydrobenzo[ b ][1,6]naphthyridine-4-carboxamide ( 4a ), gave the same results.

Leslie W. Deady - One of the best experts on this subject based on the ideXlab platform.

  • Novel annulated products from aminonaphthyridinones
    Tetrahedron, 2006
    Co-Authors: Leslie W. Deady, Shane M. Devine
    Abstract:

    Abstract 2-(4-Methoxyphenyl)-1-oxo-1,2-dihydro-1,6-naphthyridine-4-carboxamide ( 4c ) underwent Hofmann rearrangement with iodobenzene diacetate in methanol to give the corresponding 4-amino compound ( 6c ). This, when reacted with 2,4-pentanedione and then hot phosphoryl chloride (attempted Combes Synthesis) gave a new heterocyclic system, 6-(4-methoxyphenyl)-2-methylpyrido[3,2- c ]pyrrolo[2,3- e ]azocin-7(6 H )-one ( 9c ). This showed typical pyrrole-type reactivity at the 3-position. Alternatively, an attempt to convert the 4-NH 2 in 6c to 4-OH by diazotization gave, instead, a [1,2,3]triazolo[1,5- a ]pyridine-3-carboxaldehyde ( 16c ). The same series of reactions on a benzo analog, 2-methyl-1-oxo-1,2-dihydrobenzo[ b ][1,6]naphthyridine-4-carboxamide ( 4a ), gave the same results.