Article
Chemistry, Multidisciplinary
Shantonu Roy, Sudip Karmakar, Imtiaj Mondal, Koushik Naskar, Writhabrata Sarkar, Indubhusan Deb
Summary: A simple and sustainable electrochemical method has been developed for the direct synthesis of C9-functionalized N-alkyl-acridanes from acridanes and benzo fused lactones. This reaction proceeds under metal- and external oxidant-free conditions at ambient temperature, and provides good to excellent yields. The anodic oxidation of acridanes allows for a broad substrate scope and high functional-group tolerance, enabling the synthesis of a wide range of fluorescence-active acridanes with high quantum yields.
CHEMICAL COMMUNICATIONS
(2023)
Review
Chemistry, Organic
Rasmi P. Bhaskaran, Kalinga H. Nayak, Mariswamy K. Sreelekha, Beneesh P. Babu
Summary: Transition metal-catalysed C-H functionalization reactions using copper catalysts have become an efficient and green method for constructing carbon-carbon and carbon-heteroatom bonds. Intramolecular dehydrogenative coupling reactions offer a direct route to complex polycyclic scaffolds. This review focuses on the development and applications of copper-based intramolecular dehydrogenative coupling reactions.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Rongrong Zhao, Simiaomiao Wen, Hao Fu, Mengna Liu, Qixing Liu, Haifeng Zhou
Summary: A simple and efficient synthesis method for various compounds through intramolecular acceptorless dehydrogenative coupling has been achieved using bis(2-methoxyethyl)ether and molecular oxygen. This method does not require an external initiator, catalyst, or additive. The scope of this method was demonstrated through twenty-nine examples and a gram-scale reaction, and control experiments supported a possible reaction pathway.
Article
Chemistry, Organic
Sanjay Yadav, Jagadeesh Babu Nanubolu, Surisetti Suresh
Summary: This Letter presents a simple and effective method for accessing a variety of phenanthro[9,10-b]furan and 1H-dibenzo[e,g]indole derivatives. The method involves a carbenecatalyzed intramolecular Stetter reaction followed by a Paal-Knorr reaction, and has been demonstrated to be applicable on a gram scale and for postsynthetic transformations.
Article
Chemistry, Applied
Manman Wang, Mengyu Wu, Rui Ma, Kai Chen, Chuan Zhu, Chao Feng
Summary: A dehydrogenative fluorination method has been developed for the synthesis of multi-substituted trifluoromethylalkenes from various gem-difluoroalkenes using only electrophilic fluorination reagent NFSI. The reaction is tolerant to a wide range of functional groups, thereby complementing the existing synthetic protocols. Additionally, a visible-light-promoted stereoinversion strategy was discovered to obtain E-isomer enriched products.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Organic
Chen Su, Wen-Hua Xu, Rui-Li Guo, Xing-Long Zhang, Xue-Qing Zhu, Ya-Ru Gao, Yong-Qiang Wang
Summary: This study developed a novel method for the synthesis of aporphine analogues, utilizing an intramolecular dehydrogenative coupling of two inert aryl C-H bonds. The method not only exhibits high compatibility with various functional groups, but has also been further applied for the synthesis of natural products aporphine and zenkerine.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Xingwei Cai, Yang Shen, Wei Li, Wentao Zhan, Fanjun Zhang, Chen Xu, Heng Song
Summary: In this study, an efficient tungsten-catalyzed homogeneous system was developed for the selective synthesis of various azoaromatics, azoxyaromatics, and 2-substituted indolone N-oxides from anilines. This was achieved by regulating the reaction solvent with peroxide as a terminal oxidant under additive-free conditions. These findings not only provide an experimental framework for exploring tungsten catalysis in organic synthesis but also offer an efficient and convenient tactic for the selective oxidation of anilines.
Article
Chemistry, Multidisciplinary
Satoshi Kusaka, Toshimichi Ohmura, Michinori Suginome
Summary: Aryl 2-silyloxyprop-1-yl ethers underwent intramolecular C(sp(2))-H/C(sp(3))-H cross-dehydrogenative coupling in the presence of Ir/(S)-DTBM-SEGPHOS catalyst, producing enantioselective 3-methyl-3-silyloxy-2,3-dihydrobenzfurans with up to 99% ee.
Article
Chemistry, Multidisciplinary
Seydou Kassamba, Alejandro Perez-Luna, Franck Ferreira, Muriel Durandetti
Summary: Intramolecular alkyne germylzincation allows for the synthesis of a diverse range of germoles from triarylhydrogermanes. The reaction involves the activation of Ge-H bond, leading to the formation of a heteroarylzinc intermediate, which can then undergo post-functionalization reactions.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Organic
Kuei-Wei Chiu, Yu-Hsun Tseng, Ying-Xin Li, Rong-Jie Chein
Summary: In this study, a novel biomimetic synthesis of clavicipitic acid diastereomers was reported, utilizing a DDQ-mediated crossdehydrogenative coupling (CDC) reaction. The synthesis involved Suzuki coupling for prenylation and an intramolecular CDC reaction for the construction of the azepinoindole core. The trans isomer was obtained as the major product, and the two diastereomers were separable. The CDC reaction conditions were investigated, and a plausible mechanism for diastereoselectivity was proposed.
Article
Chemistry, Organic
Subrata Sahoo, Shantanu Pal
Summary: An efficient and atom-economical palladium-catalyzed intramolecular cross dehydrogenative coupling (CDC) reaction has been developed for constructing highly pi-conjugated compounds using molecular oxygen as sole oxidant. The method has wide substrate scope, good functional group tolerance, and can generate fluorescence active compounds with high quantum yield. Additionally, the synthetic versatility of the method is showcased through Fe-catalyzed reductive isoxazole ring cleavage towards heteropolycyclic compounds.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Applied
Subhasish Ray, Vipin Kumar, Saurabh Singh, Krishanu Bandyopadhyay, Satyen Saha, Maya Shankar Singh
Summary: A cascade one-pot strategy has been developed for the construction of 31 examples of furo-fused quinoxalines in high yields. The reaction utilizes readily accessible beta-ketothioamides and quinoxalin-2-ones under TBHP mediated conditions at room temperature. Mechanistic studies have revealed the seamless integration of intermolecular radical coupling and intramolecular cyclization through desulfhydration of C=S bond cleavage. The process is highly attractive due to the generation of H2S as the only by-product. Furthermore, the photophysical behavior of the furo-fused quinoxalines has been investigated.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Organic
Xiao-De An, Da-Ying Shao, Bin Qiu, Jian Xiao
Summary: An unprecedented cross-dehydrogenative coupling reaction of two C(sp(3))-H bonds to form ninemembered rings via hydride transfer has been developed. This methodology offers atom and step economy, metal-free and redox-neutral conditions, and water as the byproduct, making it applicable even with decomposed aldehydes.
Article
Chemistry, Organic
Xiao-De An, Da-Ying Shao, Bin Qiu, Jian Xiao
Summary: An unprecedented hydride transfer-triggered cross-dehydrogenative coupling of two C(sp(3))-H bonds to target nine membered rings has been developed. Salient features of this methodology include atom and step economy and metal-free and redox-neutral conditions, with water as the byproduct and proceeding well even with decomposed aldehydes.
Article
Chemistry, Organic
Yu Chen, Hairong Lyu, Yangjian Quan, Zuowei Xie
Summary: The study presents the first example of iron-catalyzed regioselective intramolecular C-H/B-H dehydrogenative coupling, resulting in unprecedented C,B-substituted carborane-fused phenanthroline derivatives. The 8-aminoquinoline type auxiliaries not only act as bidentate directing groups but also cleverly become the core part of the final products. The mechanistic hypothesis includes B-H activation, directing group rotation promoted by trans effect, C-H activation, and reductive elimination.
Article
Chemistry, Multidisciplinary
Amol P. Jadhav, V. U. Bhaskara Rao, Pradeep Singh, R. G. Gonnade, Ravi P. Singh
CHEMICAL COMMUNICATIONS
(2015)
Article
Chemistry, Organic
V. U. Bhaskara Rao, Krishna Kumar, Ravi P. Singh
ORGANIC & BIOMOLECULAR CHEMISTRY
(2015)
Article
Chemistry, Organic
Amol P. Jadhav, Devalina Ray, V. U. Bhaskara Rao, Ravi P. Singh
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2016)
Article
Chemistry, Organic
V. U. Bhaskara Rao, Krishna Kumar, Tamal Das, Kumar Vanka, Ravi P. Singh
JOURNAL OF ORGANIC CHEMISTRY
(2017)
Article
Chemistry, Organic
V. U. Bhaskara Rao, Amol P. Jadhav, Dnyaneshwar Garad, Ravi P. Singh
Article
Biochemistry & Molecular Biology
Kamalika Banerjee, Ruchika Bhat, V. U. Bhaskara Rao, Anshu Nain, Kartik Lakshmi Rallapalli, Sohona Gangopadhyay, R. P. Singh, Manidipa Banerjee, Bhyravabhotla Jayaram
Article
Multidisciplinary Sciences
Chunfa Xu, V. U. Bhaskara Rao, Julia Weigen, Charles C. J. Loh
NATURE COMMUNICATIONS
(2020)
Article
Chemistry, Multidisciplinary
V. U. Bhaskara Rao, Caiming Wang, Daniel P. Demarque, Corentin Grassin, Felix Otte, Christian Merten, Carsten Strohmann, Charles C. J. Loh
Summary: Site-selective functionalization is a significant synthetic strategy in organic synthesis. Chiral catalysis has been used to control the site selectivity in complex carbohydrate functionalizations, providing new routes to biologically relevant glycosides. However, the availability of robust catalytic systems to overcome multiple stereoselectivity challenges remains limited. In this study, we present a synergistic chiral Rh(I)- and organoboron-catalysed protocol for the synthesis of challenging but biologically relevant arylnaphthalene glycosides. Our method employs chiral Rh(I) catalysis for site-selective carbohydrate functionalization and demonstrates the utility of boronic acid as a compatible co-catalyst. The success of our method depends on the judicious choice of a suitable organoboron catalyst, and we show that multiple aspects of stereocontrol are simultaneously operative.
