@article { ISI:000356324000001, title = {Radical-mediated dehydrative preparation of cyclic imides using (NH4)(2)S2O8-DMSO: application to the synthesis of vernakalant}, journal = {Beilstein Journal of Organic Chemistry}, volume = {11}, year = {2015}, month = {JUN}, pages = {1008-1016}, publisher = {BEILSTEIN-INSTITUT}, address = {TRAKEHNER STRASSE 7-9, FRANKFURT AM MAIN, 60487, GERMANY}, abstract = {

Ammonium persulfate-dimethyl sulfoxide (APS-DMSO) has been developed as an efficient and new dehydrating reagent for a convenient one-pot process for the synthesis of miscellaneous cyclic imides in high yields starting from readily available primary amines and cyclic anhydrides. A plausible radical mechanism involving DMSO has been proposed. The application of this facile one-pot imide forming process has been demonstrated for a practical synthesis of vernakalant.

}, keywords = {APS-DMSO, imides, practical synthesis, radical-mediated, vernakalant}, issn = {1860-5397}, doi = {10.3762/bjoc.11.113}, author = {Garad, Dnyaneshwar N. and Tanpure, Subhash D. and Mhaske, Santosh B.} } @article { ISI:000380182400037, title = {Radical beckmann rearrangement and its application in the formal total synthesis of antimalarial natural product isocryptolepine via C-H activation}, journal = {Organic Letters}, volume = {18}, number = {14}, year = {2016}, month = {JUL}, pages = {3450-3453}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

The Beckmann rearrangement of ketoximes, mediated by ammonium persulfate-dimethyl sulfoxide as a reagent, has been achieved under neutral conditions. Based on the radical trapping and O-18-labeling experiments, the transformation follows a mechanism involving a radical pathway. The scope and generality of the developed protocol has been demonstrated by 19 examples. The developed protocol and Pd-catalyzed intramolecular double C-H activation were used as key steps in the formal total synthesis of antimalarial natural product isocryptolepine.

}, issn = {1523-7060}, doi = {10.1021/acs.orglett.6b01634}, author = {Mahajan, Pankaj S. and Humne, Vivek T. and Tanpure, Subhash D. and Mhaske, Santosh B.} } @article {45438, title = {Ruthenium-catalyzed regioselective alkenylation/tandem hydroamidative cyclization of unmasked quinazolinones using terminal alkynes}, journal = {Journal of Organic Chemistry}, volume = {83}, year = {2018}, month = {AUG}, pages = {8906-8913}, type = {Article}, abstract = {

Ruthenium-catalyzed amide directed C-sp2-H activation of the quinazolinone scaffold has been demonstrated, leading to the selective mono- or dialkenylation in moderate to good yields to achieve medicinally important stilbene containing quinazolinones. The terminal allcyne is utilized as a coupling partner, which resulted in the selective trans-alkene formation. Electron-deficient phenylacetylenes facilitate alkenylation followed by tandem hydroamidation of the newly generated trans double bond to provide novel quinazolinone alkaloids related to the Luotonine class of natural products.

}, doi = {10.1021/acs.joc.8b01143}, author = {Viveki, Amol B. and Mhaske, Santosh B.} } @article {46193, title = {Ru-catalyzed regioselective cascade annulation of acrylamides with 2-alkynoates for the synthesis of various 6-Oxo nicotinic acid esters}, journal = {Journal of Organic Chemistry}, volume = {84}, year = {2019}, month = {FEB }, pages = {1863-1870}, type = {Article}, abstract = {

Ru-catalyzed regioselective cascade annulation of acrylamides with 2-alkynoates via aza-Michael/C-H activation sequence for the synthesis of various 6-oxo nicotinic acid esters is described. The regioselectivity of the protocol has been confirmed by performing silver mediated protodecarboxylation of the corresponding 6-oxo nicotinic acid to furnish 2-pyridone. The developed protocol is copper or silver salt-free and uses inexpensive, safe, and environmentally benign peroxide-based {\textquoteleft}{\textquoteleft}oxone{\textquoteright}{\textquoteright} as the sole oxidant. A redox-neutral version of the protocol is also demonstrated.

}, issn = {0022-3263}, doi = {10.1021/acs.joc.8b02783}, author = {Garad, Dnyaneshwar N. and Mhaske, Santosh B.} } @article {49332, title = {Regio- and stereoselective construction of 1,3,5-triaroylcyclohexanes via KO t Bu-mediated cyclotrimerization of aryl vinyl ketones}, journal = {Journal of Organic Chemistry}, volume = {89}, year = {2024}, month = {NOV }, pages = {17207-17212}, type = {Article}, abstract = {

Herein, we disclose a simple one-pot method for an efficient regio- and stereoselective synthesis of 1,3,5-triaroylcyclohexanes from aryl vinyl ketones using potassium tert-butoxide. The developed protocol allows the construction of various symmetrically substituted cyclohexanes in good to excellent yields. The major product 2 also can be converted to the product 3 (all equatorial) conveniently by acid catalysis. This protocol features a good substrate scope and functional group compatibility.

}, issn = {0022-3263}, doi = {10.1021/acs.joc.4c01695}, author = {Mahale, Sachin D. and Yadav, Vinita and Gonnade, Rajesh G. and Mhaske, Santosh B.} }