1160063-18-2Relevant academic research and scientific papers
Intramolecular C-H activation through gold(I)-catalyzed reaction of iodoalkynes
Morn-Poladura, Pablo,Rubio, Eduardo,Gonzlez, Jos M.
, p. 3052 - 3055 (2015/04/14)
The cycloisomerization reaction of 1-(iodoethynyl)-2-(1-methoxyalkyl)arenes and related 2-alkyl-substituted derivatives gives the corresponding 3-iodo-1-substituted-1H-indene under the catalytic influence of IPrAuNTf2 [IPr = 1,3-bis(2,6-diisopropyl)phenylimidazol-2-ylidene; NTf2 = bis(trifluoromethanesulfonyl)imidate]. The reaction takes place in 1,2-dichloroethane at 80°C, and the addition of ttbp (2,4,6-tritert-butylpyrimidine) is beneficial to accomplish this new transformation in high yield. The overall reaction implies initial assembly of an intermediate gold vinylidene upon alkyne activation by gold(I) and a 1,2-iodine-shift. Deuterium labeling and crossover experiments, the magnitude of the recorded kinetic primary isotopic effect, and the results obtained from the reaction of selected stereochemical probes strongly provide support for concerted insertion of the benzylic C-H bond into gold vinylidene as the step responsible for the formation of the new carbon-carbon bond.
Iodoarene-Catalyzed Stereospecific Intramolecular sp3 C-H Amination: Reaction Development and Mechanistic Insights
Zhu, Chendan,Liang, Yong,Hong, Xin,Sun, Heqing,Sun, Wei-Yin,Houk,Shi, Zhuangzhi
supporting information, p. 7564 - 7567 (2015/06/30)
A new strategy is reported for intramolecular sp3 C-H amination under mild reaction conditions using iodoarene as catalyst and m-CPBA as oxidant. This C-H functionalization involving iodine(III) reagents generated in situ occurs readily at sterically hindered tertiary C-H bonds. DFT (M06-2X) calculations show that the preferred pathway involves an iodonium cation intermediate and proceeds via an energetically concerted transition state, through hydride transfer followed by the spontaneous C-N bond formation. This leads to the experimentally observed amination at a chiral center without loss of stereochemical information.
Platinum and ruthenium chloride-catalyzed cycloisomerization of 1-alkyl-2-ethynylbenzenes: Interception of π-activated alkynes with a benzylic C-H bond
Tobisu, Mamoru,Nakai, Hiromi,Chatani, Naoto
supporting information; experimental part, p. 5471 - 5475 (2009/12/06)
(Chemical Equation Presented) Air-stable and commercially available alkynophilicmetal salts, such as PtCl2, PtCl4, and [RuCl2(CO)3]2, catalyze the cycloisomerization of 1-alkyl-2-ethynylbenzenes to produce substituted indenes even at an ambient temperature. Electrophilically activated alkynes can be intercepted by simple benzylic C-Hbonds at primary, secondary, and tertiary carbon centers. Mechanistic studies, such as labeling studies and kinetic isotope and substituent effects, indicate that the cycloisomerization proceeds through the formation of a vinylidene intermediate and turnover-limiting 1,5-shift of benzylic hydrogen.
