7661-29-2Relevant articles and documents
Enantioselective Synthesis of Cyclopropanone Equivalents and Application to the Formation of Chiral β-Lactams
Jang, Yujin,Johnson, J. Drake,Jung, Myunggi,Lindsay, Vincent N. G.,Poteat, Christopher M.,Williams, Rachel G.
supporting information, p. 18655 - 18661 (2020/08/21)
Cyclopropanone derivatives have long been considered unsustainable synthetic intermediates because of their extreme strain and kinetic instability. Reported here is the enantioselective synthesis of 1-sulfonylcyclopropanols, as stable yet powerful equivalents of the corresponding cyclopropanone derivatives, by α-hydroxylation of sulfonylcyclopropanes using a bis(silyl) peroxide as the electrophilic oxygen source. This work constitutes the first general approach to enantioenriched cyclopropanone derivatives. Both the electronic and steric nature of the sulfonyl moiety, which serves as a base-labile protecting group and confers crystallinity to these cyclopropanone precursors, were found to have a crucial impact on the rate of equilibration to the corresponding cyclopropanone. The utility of these cyclopropanone surrogates is demonstrated in a mild and stereospecific formal [3+1] cycloaddition with simple hydroxylamines, leading to the efficient formation of chiral β-lactam derivatives.
Efficient and Mild Ullmann-Type N-Arylation of Amides, Carbamates, and Azoles in Water
Bollenbach, Maud,Aquino, Pedro G. V.,de Araújo-Júnior, Jo?o Xavier,Bourguignon, Jean-Jacques,Bihel, Frédéric,Salomé, Christophe,Wagner, Patrick,Schmitt, Martine
supporting information, p. 13676 - 13683 (2017/10/10)
A simple, sustainable, efficient, mild, and low-cost protocol was developed for d-glucose-assisted Cu-catalyzed Ullmann reactions in water for amides, carbamates, and nitrogen-containing heterocycles. The reaction was compatible with diverse aryl/heteroaryl iodides, giving highly substituted pyridine, indole, or indazole rings. This method offers an attractive alternative to existing protocols, because the reaction proceeds in aqueous media, occurs at or near ambient temperature, and provides the N-arylated products in good to high yields.
Synthesis of 2,3-dihydro-4(1H)-quinolones and the corresponding 4(1H)-quinolones via low-temperature fries rearrangement of N-arylazetidin-2- ones
Lange, Jens,Bissember, Alex C.,Banwell, Martin G.,Cade, Ian A.
experimental part, p. 454 - 470 (2011/10/09)
N-Arylazetidin-2-ones of the general form 1, which are readily prepared by GoldbergBuchwald-type copper-catalyzed coupling of N-unsubstituted azetidin-2-ones with the relevant aryl halide or using Mitsunobu cyclization processes, undergo smooth Fries-rearrangement in triflic acid at 018°C to give the isomeric 2,3-dihydro-4(1H)-quinolones (2). Dehydrogenation of the latter compounds using 10% Pd on C in 1.0M aqueous sodium hydroxide/propan-2-ol mixtures at ca. 82°C provides the corresponding 4(1H)-quinolones (3).
