Intramolecular C−N Bond Addition of Amides to Alkynes Using Platinum Catalyst
摘要:
The intramolecular aminoacylation of alkynes using ortho-alkynylacetanilides proceeds in very high yields in the presence of PtCl2 catalyst. This reaction provides not only a useful procedure for synthesizing 2,3-disubstituted indoles at once from ortho-alkynylaniline derivatives, but also an interesting mechanistic aspect; the intramolecular C-N bond addition of amides to alkynes takes place readily in the presence of Pt(II) catalyst.
KMnO4-mediated oxidative C N bond cleavage of tertiary amines: Synthesis of amides and sulfonamides
作者:Zhang Zhang、Yong-Hong Liu、Xi Zhang、Xi-Cun Wang
DOI:10.1016/j.tet.2019.03.047
日期:2019.5
KMnO4-mediated oxidative CN bond cleavage of tertiaryamines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.
Oxidation during reductive cyclisations using Bu3SnH
作者:W.Russell Bowman、Harry Heaney、Benjamin M. Jordan
DOI:10.1016/s0040-4020(01)96061-2
日期:1991.1
Reductivecyclisations using Bu3SnH include an “oxidation” step if the removal of an acidic proton from the intermediate cyclised radical, by Bu3SnH acting as a base, is favourable. A “pseudo” SRN1 mechanism is proposed.
如果通过Bu 3 SnH作为碱从中间环化自由基中除去酸性质子是有利的,则使用Bu 3 SnH进行的还原环化包括一个“氧化”步骤。提出了一种“伪” S RN 1机制。
Potassium <i>tert</i>-Butoxide Promoted Intramolecular Arylation via a Radical Pathway
作者:Daniela Sustac Roman、Yoko Takahashi、André B. Charette
DOI:10.1021/ol201160s
日期:2011.6.17
Potassium tert-butoxide mediated intramolecular cyclization of aryl ethers, amines, and amides was efficiently performed under microwave irradiation to provide the corresponding products in high regioisomeric ratios. The reaction proceeds via single-electron transfer to initiate the formation of an arylradical, followed by a kinetically favored 5-exo-trig and subsequent ring expansion.
Samarium(II)-mediated spirocyclization by intramolecularaddition of arylradicals onto an aromatic ring was achieved by the reaction of N-(2-iodophenyl)-N-alkylbenzamides with SmI2 in the presence of HMPA, yielding spirocyclic indolin-2-one derivatives. The ether congeners afford spirocyclic benzofuran derivatives in moderate yields by arylradicaladdition onto a benzene ring without having an electron-withdrawing
Aniline‐Type Hypervalent Iodine(III) for Intramolecular Cyclization via C−H Bond Abstraction of Hydrocarbons Containing N‐ and O‐Nucleophiles
作者:Yuna Nishiguchi、Katsuhiko Moriyama
DOI:10.1002/adsc.202100316
日期:2021.7
We developed a method for the preparation of (diacetoxyiodo)-2-(N-alkylamido)benzene as an aniline-type hypervalent iodine(III). We also achieved direct cyclizations via C−H bond abstraction, such as the Hofmann-Löffler-Freytag reaction, a direct amination, and a direct lactonization, using the aniline-type hypervalent iodine(III) to obtain corresponding products in high yields.