183312-49-4Relevant academic research and scientific papers
Synthetic method 1-2 -dihydrocyclobutene [a] naphthalene derivative and precursor thereof
-
, (2020/10/04)
The invention relates to the field of organic synthetic chemistry, in particular to a 1,2-dihydrocyclobuteno[a] naphthalene derivative and a synthesis method of a precursor thereof. The invention provides a synthesis method of allenic ketone ester. According to the synthesis method, benzene ring-connected dieneyne ketone ester is synthesized for the first time; the dieneyne ketone ester is the precursor for synthesizing the 1,2-dihydrocyclobuteno[a] naphthalene, and has the advantages of being simple, convenient, efficient, mild in reaction condition, environmentally friendly, low in cost, low energy in consumption and the like.
Trifluorosulfonylation Cascade in Allenols: Stereocontrolled Synthesis of Bis(triflyl)enones
Lázaro-Milla, Carlos,Macicior, Jon,Yanai, Hikaru,Almendros, Pedro
supporting information, p. 8983 - 8989 (2020/07/09)
Herein, we report investigations embodying the first example of reversal of the native regioselectivity in the reaction of allenols with electrophiles. The effortlessness of C?C bond formation, mild reaction conditions, neither catalysts nor light irradiation, and exquisite selectivity, both in terms of functional-group tolerance and chemo-, site-, and stereo-selectivity, converts this trifluorosulfonylation-rearrangement sequence into an appealing protocol for the preparation of novel functionalized enones. The synthetic utility of this method has been validated by the conversion of the initially prepared bis(triflyl)enones into a variety of bis(triflyl)-functionalized molecules such as 1,3-dienes, allylic alcohols, pyrroles, pyrazoles, and chromenes. Besides, DFT calculations have provided a reliable understanding of observed selectivity.
A Silver-Catalyzed Modular Intermolecular Access to 6,6-Spiroketals
Ahrens, Alexander,Heinrich, Niklas F.,Kohl, Simon R.,Hokamp, Martha,Rudolph, Matthias,Rominger, Frank,Hashmi, A. Stephen K.
, p. 5605 - 5615 (2019/12/11)
A modular synthesis of 6,6-spiroketals via silver catalysis is reported. By combining an intermolecular Michael addition and a 6-endo-dig cyclization, this cascade reaction allows the modular preparation of highly substituted 6,6-spiroketals by combining two substrate molecules. Established methods accessing this interesting substructure are complemented by this new transformation. The protocol tolerates diverse substitution patterns and functional groups. (Figure presented.).
Gold-Catalyzed Oxidative Cyclizations of { o-(Alkynyl)phenyl propargyl} Silyl Ether Derivatives Involving 1,2-Enynyl Migration: Synthesis of Functionalized 1 H-Isochromenes and 2 H-Pyrans
Zhao, Jidong,Xu, Wei,Xie, Xin,Sun, Ning,Li, Xiangdong,Liu, Yuanhong
supporting information, p. 5461 - 5465 (2018/09/13)
A new and convenient strategy for the synthesis of functionalized 1H-isochromene and 2H-pyran derivatives based on gold-catalyzed oxidative cyclizations of o-(alkynyl)phenyl propargyl ether derivatives has been developed. The reaction proceeds via gold-catalyzed highly regioselective oxidation, followed by 1,2-migration of an enynyl group and nucleophlic addition. Isocoumarins were also constructed through oxidative cleavage of the exocyclic double bond of the obtained 1H-isochromenes.
Merging [2+2] Cycloaddition with Radical 1,4-Addition: Metal-Free Access to Functionalized Cyclobuta[a]naphthalen-4-ols
Liu, Feng,Wang, Jia-Yin,Zhou, Peng,Li, Guigen,Hao, Wen-Juan,Tu, Shu-Jiang,Jiang, Bo
, p. 15570 - 15574 (2017/12/02)
A metal-free [2+2] cycloaddition and 1,4-addition sequence induced by S-centered radicals has been achieved by treating benzene-linked allene-ynes with aryldiazonium tetrafluoroborates and DABCO-bis(sulfur dioxide) in a one-pot procedure. The reaction provides a greener and more practical access to functionalized cyclobuta[a]naphthalen-4-ols with valuable applications. More than 50 examples are demonstrated with excellent diastereoselectivity and chemical yields. The reaction pathway is proposed to proceed by the following steps:[2+2] cycloaddition, insertion of SO2, 1,4-addition, diazotization, and tautomerization.
Base-Catalyzed Cyclization of 1,6-Diynyl Carboxylates Involving Propargyl-Allenyl Isomerization: Efficient Synthesis of Benzo[b]fluorene and Its Analogues
Sun, Ning,Xie, Xin,Wang, Gaonan,Chen, Haoyi,Liu, Yuanhong
supporting information, p. 1394 - 1401 (2017/04/21)
An efficient protocol for the synthesis of benzo[b]fluorenes via base-catalyzed cyclization of 1,6-diynyl carbonates, esters or ethers has been developed. The reaction likely proceeds via base-induced propargyl-allenyl isomerization followed by Schmittel-type cyclization. Heterocycle-fused fluorenes such as thiophene- or pyridine-fused substrates could also be conveniently constructed by this method. The synthetic utility of this reaction was demonstrated by the preparation of up to seven-ring fused polycyclic aromatic hydrocarbons. (Figure presented.).
Metal/Benzoyl Peroxide (BPO)-Controlled Chemoselective Cycloisomerization of (o-Alkynyl)phenyl Enaminones: Synthesis of α-Naphthylamines and Indeno[1,2-c]pyrrolones
Zhang, Fangfang,Qin, Zhengchen,Kong, Lingkai,Zhao, Yulei,Liu, Yuanyuan,Li, Yanzhong
, p. 5150 - 5153 (2016/10/14)
Synthetic methods involving chemoselective tandem reactions for the synthesis of α-naphthylamines and indeno[1,2-c]pyrrolones starting from (o-aklynyl)phenyl enaminones are described. When reactions were carried out in N,N-dimethylformamide (DMF) using a AgNO3 catalyst, α-naphthylamines were obtained in up to 89% isolated yields within 2 h. Whereas indeno[1,2-c]pyrrolones were produced in high isolated yields in the presence of benzoyl peroxide (BPO) and CuCl catalysis.
Gold catalysis: β-ketonaphthalenes via molecular gymnastics of 1,6-diyne-4-en-3-ols
Lauterbach, Tobias,Arndt, Sebastian,Rudolph, Matthias,Rominger, Frank,Hashmi, A. Stephen K.
, p. 1755 - 1761 (2013/07/11)
1,6-Diyne-4-en-3-ols with one terminal alkyne were applied as test substrates for a possible dual catalyzed cyclization. Instead of a dual catalysis cycle, naphthyl ketone derivatives were obtained as single products. The regioselectivity of the obtained products is unprecedented. Instead of the expected naphthyl ketones bearing the keto group in the α-position, the keto group is positioned in the ss-position of the naphthyl skeleton by a complex rearrangement of the starting materials. Copyright
Gold-catalyzed cascade friedel-crafts/furan-yne cyclization/heteroenyne metathesis for the highly efficient construction of phenanthrene derivatives
Chen, Yifeng,Li, Guijie,Liu, Yuanhong
, p. 392 - 400 (2011/04/22)
A rapid access to highly substituted phenanthrenyl ketones through gold-catalyzed cyclization of 1,6-diyn-4-en-3-ols with furans has been developed. Gold catalysts are effective to catalyze three cascade processes involving Friedel-Crafts/furan-yne cyclization/heteroenyne metathesis through C-O bond and alkyne activation. This method offers several advantages such as high selectivities and easily accessible starting materials.
The thermal C2-C6/[2 + 2] cyclisation of enyne-allenes: Reversible diradical formation
Cinar, Mehmet Emin,Vavilala, Chandrasekhar,Fan, Jian,Schmittel, Michael
scheme or table, p. 3776 - 3779 (2011/06/24)
New enyne-allenes, structurally designed toward the thermal C 2-C6/[2 + 2] cyclisation mode, were prepared and characterised, one of them even by X-ray crystallography. The mechanism of their transformation to formal [2 + 2] cycloadducts was interrogated by trapping experiments and DFT computations. The results support a stepwise mechanism that involves the reversible formation of the C2-C6 diradical intermediate.
