Effect of Amine Nature on Reaction Mechanism: Aminolyses of <i>O</i>-4-Nitrophenyl Thionobenzoate with Primary and Secondary Amines
作者:Ik-Hwan Um、Seung-Eun Lee、Hey-Jin Kwon
DOI:10.1021/jo0259360
日期:2002.12.1
determined for the reactions of 2 with all the primary and secondaryamines studied. The k(1) value is larger for the reaction with the primaryamine than for the reaction with the isobasic acyclic secondaryamines, while the k(-)(1) value is much larger for the latter reaction than for the former reaction. The k(3) value for the reaction with secondaryamine is independent of the amine basicity. The small
Sequential reactions of thioiminium salts generated from thioamides and methyl triflate with organolithium and -magnesium reagents proceed smoothly to give tertiary propargylamines in moderate to high yields. In all cases, two different organometallic reagents are incorporated into the starting thioamides.
Reactions of Hexadehydro-Diels–Alder (HDDA)-Derived Benzynes with Thioamides: Synthesis of Dihydrobenzothiazino-Heterocyclics
作者:Vignesh Palani、Junhua Chen、Thomas R. Hoye
DOI:10.1021/acs.orglett.6b03199
日期:2016.12.16
Reaction of thioamides (e.g., II) with benzynes generated by the hexadehydro-Diels–Alder (HDDA) cycloisomerization (e.g., I) produces dihydrobenzothiazines (e.g., III). It is postulated that the reaction proceeds via benzothietene (cf. IV) and o-thiolatoaryliminium (cf. V) intermediates and that the latter undergoes intramolecular 1,3-hydrogen atom migration to produce the penultimate isomeric iminium