- Redox-triggered interconversion between piperidine chair conformations in a Cu(I/II) complex
-
A redox-induced six-membered ring chair-chair conformational interconversion in a copper-coordinated trans-piperidine tripodal ligand is demonstrated. Each group of the 1,2,3-substituted ring can potentially ligate the metal; two equatorial groups ligate the metal in the CuI state leaving a disassociated, axial group. However, all three groups (two axial and one equatorial) ligate the metal in the CuII state. Exciton-coupled circular dichroism (ECCD) and 2D NMR were used to characterize the structures.
- Zhang, Jing,Canary, James W.
-
-
Read Online
- Iron-catalyzed tandem oxidative coupling and acetal hydrolysis reaction to prepare formylated benzothiazoles and isoquinolines
-
The aldehyde group is one of the most versatile intermediates in synthetic chemistry, and the introduction of an aldehyde group into heteroarenes is important for the transformation of molecular structure. Herein, we achieved the direct formylation of benzothiazo/les and isoquinolines. The reaction features a novel iron-catalyzed Minisci-type oxidative coupling process using commercially available 1,3-dioxolane as a formylated reagent followed by acetal hydrolysis without a separation process. The reaction can be performed under exceedingly mild reaction conditions and exhibits broad functional group tolerance.
- Wu, Yue,Guo, Peng,Chen, Long,Duan, Weijie,Yang, Zengzhuan,Wang, Tao,Chen, Ting,Xiong, Fei
-
supporting information
p. 3271 - 3274
(2021/04/07)
-
- Methanol as a formylating agent in nitrogen heterocycles
-
A radical mediated C-H direct formylation of N-heteroarenes with methanol is reported. The reaction features a novel iron-catalyzed Minisci oxidative coupling process using commercially available methanol as a formylating reagent. It effectively solved the long-standing problems associated with using methanol as a formylating reagent in these types of reactions. Compared to the traditional Minisci C-H formylation methods, this protocol is highly atom-economical, simple to operate, and environmentally friendly and shows good functional group tolerance. This Minisci formylation strategy is a straightforward approach for the late-stage functionalization of N-heteroarenes. This journal is
- Xu, Zhengbao,Zhang, Lizhi
-
p. 9476 - 9482
(2021/11/17)
-
- Photoredox-Catalyzed Redox-Neutral Minisci C?H Formylation of N-Heteroarenes
-
We report a protocol for redox-neutral Minisci C?H formylation of N-heteroarenes using 1,3-dioxoisoindolin-2-yl 2,2-diethoxyacetate as a formyl equivalent at room temperature. This scalable benchtop protocol offers a distinct advantage over traditional reductive carbonylation and Minisci C?H formylation methods in not requiring the use of carbon monoxide, pressurized gas, a stoichiometric reductant, or a stoichiometric oxidant. (Figure presented.).
- Dong, Jianyang,Wang, Xiaochen,Song, Hongjian,Liu, Yuxiu,Wang, Qingmin
-
supporting information
p. 2155 - 2159
(2020/02/11)
-
- Surgical Cleavage of Unstrained C(sp3)?C(sp3) Bonds in General Alcohols for Heteroaryl C?H Alkylation and Acylation
-
We reported herein a predictable and surgical cleavage of carbon-carbon bond in alcohols. A wide range of 1°, 2° and 3° alcohols including sugars and steroids without ring strain or steric hindrance were all compatible with this system. Also it offered a green and practical strategy for generation of alkyl/acyl radicals using alcohols as the sources. Besides, the features of visible-light-initiation, catalyst and metal free, excellent selectivity and mild conditions make it valuable and attractive. (Figure presented.).
- Wang, Yaxin,Yang, Le,Liu, Shuai,Huang, Lixia,Liu, Zhong-Quan
-
supporting information
p. 4568 - 4574
(2019/09/04)
-
- Photoredox-Catalyzed Decarboxylative C-H Acylation of Heteroarenes
-
A mild, environmentally friendly, and regioselective acylation of heterocycles with inexpensive carboxylic acids is reported via photoredox catalysis. The strategy is highlighted with good functional group tolerance and substrate scope which could rapidly
- Jia, Wei,Jian, Yong,Huang, Binbin,Yang, Chao,Xia, Wujiong
-
supporting information
p. 1881 - 1886
(2018/08/28)
-
- Hydroxymethylation of Quinolines with Na2S2O8 by a Radical Pathway
-
Quinolines and isoquinolines were treated with Na2S2O8 in a mixture of methanol and water at 70 °C to form hydroxymethylated quinolines and isoquinolines in good to moderate yields, under transition-metal-free conditions. The formed hydroxymethyl group was smoothly converted into aldehyde, ester, amide, bromomethyl, (N,N-diethylamino)methyl, cyano, and tetrazole groups, in good yields.
- Zhou, Luan,Okugawa, Naoyuki,Togo, Hideo
-
p. 6239 - 6245
(2017/11/15)
-
- Synthesis and anti-norovirus activity of pyranobenzopyrone compounds
-
During the last decade, noroviruses have gained media attention as the cause of large scale outbreaks of gastroenteritis on cruise ships, dormitories, nursing homes, etc. Although noroviruses do not multiply in food or water, they can cause large outbreaks because approximately 10-100 virions are sufficient to cause illness in a healthy adult. Recently, it was shown that the activity of acyl-coenzyme A:cholesterol acyltransferase-1 (ACAT1) enzyme may be important in norovirus infection. In search of anti-noroviral agents based on the inhibition of ACAT1, we synthesized and evaluated the inhibitory activities of a class of pyranobenzopyrone molecules containing amino, pyridine, substituted quinolines, or 7,8-benzoquinoline nucleus. Three of the sixteen evaluated compounds possess ED50 values in the low micrometer range. 2-Quinolylmethyl derivative 3A and 4-quinolylmethyl derivative 4A showed ED50 values of 3.4 and 2.4 μM and TD50 values of >200 and 96.4 μM, respectively. The identified active compounds are suitable for further modification for the development of anti-norovirus agents.
- Pokhrel, Laxman,Kim, Yunjeong,Nguyen, Thi D.T.,Prior, Allan M.,Lu, Jianyu,Chang, Kyeong-Ok,Hua, Duy H.
-
supporting information; experimental part
p. 3480 - 3484
(2012/07/03)
-
- A new, convenient, highly selective free-radical hydroxymethylation of heteroaromatic bases by persulfate oxidation of ethylene glycol and glycerol, catalysed by AgNO3
-
A new, convenient and selective source of hydroxymethyl ( .CH2OH) radical has been developed by persulfate oxidation of ethylene glycol with AgNO3 catalysis. The .CH 2OH radical is selectively trapped
- Minisci, Francesco,Porta, Ombretta,Recupero, Francesco,Punta, Carlo,Gambarotti, Cristian,Pruna, Barbara,Pierini, Monica,Fontana, Francesca
-
p. 874 - 876
(2007/10/03)
-
- A facile preparation of pyridine- and quinoline-carboxaldehydes by palladium catalysed carbonylation
-
A range of pyridine and quinoline carboxaldehydes have been prepared by palladium catalysed carbonylation from the corresponding bromides and triflates.
- Holzapfel, Cedric W.,Ferreira, Alta C.,Marais, Wilhelmina
-
p. 218 - 220
(2007/10/03)
-
- 1-(benzoylamino)-3-methylimidazolium chlorochromate (BAMICC), a new selective and mild reagent for the oxidation of allylic and benzylic alcohols
-
A new mild chromium(VI) oxidizing reagent, the 1-(benzoylamino)-3-methylimidazolium chlorochromate (BAMICC) has been prepared as a stable yellow-orange solid which selectively oxidizes allylic and benzylic alcohols, including those bearing basic nitrogens, to carbonyl compounds.
- Martinez, Yolanda,De Las Heras, Maria A.,Vaquero, Juan J.,Garcia-Navio, Jose L.,Alvarez-Builla, Julio
-
p. 8513 - 8516
(2007/10/02)
-
- A novel and mild source of carboncentered radicals by iodosobenzene diacetate (IBDA) and sodium azide from alcohols, ethers, aldehydes, amides and alkyl iodides
-
A radical process for the thermal decomposition of IBDA in the presence of sodium azide; by this method, carbon centered radicals can be generated either by hydrogen abstraction from the solvent (an alcohol, an ether, an aldehyde or formamide) or by iodin
- Fontana, Francesca,Minisci, Francesco,Yan, Yong Ming,Zhao, Lihua
-
p. 2517 - 2520
(2007/10/02)
-
- POLAR EFFECTS IN FREE-RADICAL REACTIONS. NEW CATALYTIC PROCESSES IN THE SUBSTITUTION OF HETEROATOMIC BASES BY NUCLEOPHILIC FREE-RADICALS
-
New catalytic hydroxymethylation, dioxanylation and acylation of protonated heteroatomic bases by methanol, dioxan, and aldehydes, respectively, are reported.The importance of the polar effects in determining reactivity, selectivity, and catalytic efficie
- Minisci, Francesco,Vismara, Elena,Fontana, Francesca,Redaelli, Daniele
-
p. 363 - 368
(2007/10/02)
-
- HYDROXYLAMINE-O-SULPHONIC ACID-INDUCED SUBSTITUTION OF HETEROAROMATIC BASES BY α-OXYALKYL RADICALS FROM ALKYL ETHERS
-
Thermal and Fe(II)-catalyzed decomposition of hydroxylamine-O-sulphonic acid (HOSA) in the presence of alkyl ethers and protonated heteroaromatic bases affords α-alkylation products of the base with high selectivity and yield.The reaction is a radical redox-chain process involving the formation of ammoniumyl radicals ( NH3(+.)), preferential hydrogen abstraction from α C-H bonds of ethers by NH3(+.), trapping of the nucleophilic alkyl radical produced by the base and oxidation of the pyridinyl radical adduct by HOSA or Fe(III).Thermal initiation appears to be somewhat less efficient than Fe(II) or Fe(III) initiation.The α-oxyalkylation process appears to be strongly affected by the reducing properties of the carbon free radicals, their reversibility in the addition to the base and by hydrolysis of HOSA.The selectivity of the hydrogen atom abstraction by NH3(+.) and the competition of the free radical intermediates between addition to the base and oxidation by Fe(III) have been investigated.
- Citterio, Attilio,Casucci, Domenico,Gentile, Anna,Serravalle, Marco,Ventura, Susanna
-
p. 319 - 324
(2007/10/02)
-
- STUDIES ON PYRIMIDINE DERIVATIVES. XXII. SITE-SELECTIVE OXIDATION OF DIMETHYLPYRIMIDINES WITH SELENIUM DIOXIDE TO PYRIMIDINE-MONOALDEHYDES
-
The oxidation of 2,4-dimethylquinoline and its 1-oxide with an equimolecular amount of selenium dioxide in boiling dioxane afforded 4-methylquinoline-2-carbaldehyde and its 1-oxide, respectively.This oxidation was applicable to the selective preparation o
- Sakamoto, Takao,Sakasai, Takeji,Yamanaka, Hiroshi
-
p. 2485 - 2490
(2007/10/02)
-