Domino construction of a bullataketal core via double bond cleavage in activated dihydrofurans

2018 ◽  
Vol 5 (10) ◽  
pp. 1655-1663 ◽  
Author(s):  
Konstantin L. Ivanov ◽  
Ivan M. Vatsouro ◽  
Stanislav I. Bezzubov ◽  
Mikhail Ya. Melnikov ◽  
Ekaterina M. Budynina

A new rapid approach to structurally challenging and biologically relevant methanobenzodioxepines was developed via a Brønsted acid-triggered domino transformation of 3-carbonyl-4,5-dihydrofurans, substituted with MOM-protected o-hydroxyaryls at the C4 atom.

Synthesis ◽  
2017 ◽  
Vol 49 (16) ◽  
pp. 3609-3618 ◽  
Author(s):  
Yanzhong Li ◽  
Yulei Zhao ◽  
Yang Yuan ◽  
Lingkai Kong ◽  
Fangfang Zhang

A novel gold(I)/Brønsted acid sequential catalyzed/promoted procedure to synthesize 1-alkyl-3-(2-oxo-2-aryl/alkyl-ethyl)indolin-2-ones under mild reaction conditions is developed. This methodology is realized by relay actions of gold and a Brønsted acid in a one-pot multistep manner. The gold(I)-catalyzed chemoselective C(sp2)-H functionalization of enaminones and Brønsted acid promoted cleavage of the C=C bond are integrated effectively. Based on the results of control experiments and ESI-MS analysis, a possible reaction mechanism is proposed.


RSC Advances ◽  
2015 ◽  
Vol 5 (104) ◽  
pp. 85646-85651 ◽  
Author(s):  
Guanshuo Shen ◽  
Haifeng Zhou ◽  
Peng Du ◽  
Sensheng Liu ◽  
Kun Zou ◽  
...  

Synlett ◽  
2018 ◽  
Vol 29 (17) ◽  
pp. 2298-2300 ◽  
Author(s):  
Benjamin List ◽  
Grigory Shevchenko ◽  
Stefanie Dehn

We report a Brønsted acid mediated direct α-hydroxylation of cyclic α-branched ketones via a tandem aminoxylation/N–O bond-cleavage process. Nitrosobenzene is used as the oxidant and subsequently promotes the liberation of the free alcohol. The desired products could be isolated in moderate to good yields at a maximum tested scale of 10 mmol. Derivatizations of the obtained products are presented.


2016 ◽  
Vol 52 (15) ◽  
pp. 3215-3218 ◽  
Author(s):  
Isai Ramakrishna ◽  
Harekrishna Sahoo ◽  
Mahiuddin Baidya

A Brønsted acid mediated N–O bond cleavage for α-amination of ketones has been developed through the nitroso aldol reaction of less-reactive aromatic nitroso compounds and silyl enol ethers having a disilane (–SiMe2TMS) backbone.


Synlett ◽  
2021 ◽  
Author(s):  
Andreas Berkefeld ◽  
Ivana Fleischer ◽  
Prasad M. Kathe

AbstractThis report discloses the deallylation of O- and N-allyl functional groups by using a combination of a Ni-H precatalyst and excess Brønsted acid. Key steps are the isomerization of the O- or N-allyl group through Ni-catalyzed double-bond migration followed by Brønsted acid induced O/N–C bond hydrolysis. A variety of functional groups are tolerated in this protocol, highlighting its synthetic value.


Synlett ◽  
2020 ◽  
Author(s):  
Nuno Maulide ◽  
Bogdan R. Brutiu ◽  
Immo Klose

A method for the Brønsted acid promoted desulfination of aryl sulfoxides is presented. In the presence of a thiol, electron-rich sulfoxides undergo C–S bond cleavage to give the corresponding protodesulfinated arenes and disulfides.


Sign in / Sign up

Export Citation Format

Share Document