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1.
Qiangqiang Yan Tangxin Xiao Zhanxiang Liu Yuhong Zhang 《Advanced Synthesis \u0026amp; Catalysis》2016,358(16):2707-2711
Cobalt‐catalyzed C−H amination of arenes with alkylamines by the assistance of 8‐aminoquinoline as auxiliary through sp2 C−H bond functionalization has been achieved. Attractive features of this protocol include the low loading of the cobalt catalyst and the readily available reagents.
2.
Yingxiao Cai Xin Qian Corinne Gosmini 《Advanced Synthesis \u0026amp; Catalysis》2016,358(15):2427-2430
An efficient and easy method for C −C homocoupling was developed using cobalt bromide as catalyst. A series of functionalized alkyl bromides and alkyl chlorides were coupled in high yields under mild conditions. This reaction seems to involve a radical intermediate.
3.
Chenggui Wu Zhenxing Liu Zhikun Zhang Fei Ye Guisheng Deng Yan Zhang Jianbo Wang 《Advanced Synthesis \u0026amp; Catalysis》2016,358(15):2480-2488
A new synthetic method for α‐alkynyl‐α,β‐unsaturated esters is presented herein. The method is based on a copper(I)‐catalyzed three‐component reaction of a terminal alkyne, diazoesters and aldehydes. The reaction is featured by mild conditions, high yields and excellent stereoselectivity. Cu(I) carbene migratory insertion is proposed as the key step in the transformation.
4.
Fuhong Xiao Shuqing Chen Cheng Li Huawen Huang Guo‐Jun Deng 《Advanced Synthesis \u0026amp; Catalysis》2016,358(23):3881-3886
A copper‐catalyzed three‐component (arenes, iodohydrocarbon, and sulfur powder) synthesis of substituted aryl sulfides has been developed. Water is used as the green solvent in a simple and environmentally friendly procedure. Various functional groups attached to the substrates were well tolerated in this process to afford the corresponding products in moderate to good yields.
5.
A catalytic system comprising the inexpensive cobalt(II) acetylacetonate [Co(acac)2] and an N‐heterocyclic carbene (NHC) ligand enabled versatile C−H arylations by oxazoline assistance. The broadly applicable, low‐valent cobalt catalyst displayed a wide substrate scope, and even proved applicable to challenging C−H alkylations with β‐hydrogen‐containing primary and secondary alkyl chlorides. The power of the cobalt‐catalyzed C−H arylation protocol was among others reflected by facile C−H activation at a room temperature of 23 °C, and efficient late‐stage diversification, providing access to bioactive biaryls.
6.
Longyang Dian Hui Zhao Daisy Zhang‐Negrerie Yunfei Du 《Advanced Synthesis \u0026amp; Catalysis》2016,358(15):2422-2426
A cobalt‐catalyzed regioselective C‐3 alkylation of coumarins was realized under mild reaction conditions, during which a variety of substituted coumarins including those containing sensitive functional groups could smoothly undergo the selective C(sp2)−C(sp3) bond formation with a series of cyclic or straight‐chain alkyl ethers.
7.
8.
Wengang Xu Jie Hui Pek Naohiko Yoshikai 《Advanced Synthesis \u0026amp; Catalysis》2016,358(15):2564-2568
We report here that a cobalt catalyst generated from a cobalt(II) salt and a ligand using magnesium metal is capable of promoting hydroarylation reactions through chelation‐assisted C−H activation. With the appropriate choice of the ligand and other reaction conditions, ketimine‐ or aldimine‐directed branched selective hydroarylations of styrenes and ketimine‐directed hydroarylations of vinylsilane have been achieved. The reported catalytic systems may serve as more convenient alternatives to previously developed catalytic systems employing Grignard reagents as reducing agents.
9.
Rajnikanth Sunke E. V. Venkat Shivaji Ramarao Suresh Babu Nallapati Raghavender Medisetti Pushkar Kulkarni Ravi Kumar Kapavarapu Ramudu Bankala Kishore V. L. Parsa Manojit Pal 《Advanced Synthesis \u0026amp; Catalysis》2016,358(20):3201-3205
A copper‐catalyzed new domino reaction allowed the facile and direct construction of the dibenzo‐fused azepinone ring leading to an array of novel small molecules. The co‐catalyst, ligand or additive free one‐pot method afforded a unique class of functionalized derivatives, one of which showed encouraging PDE4 inhibition in vitro and apoptosis in vivo.
10.
Valentin Magn Florent Blanchard Angela Marinetti Arnaud Voituriez Xavier Guinchard 《Advanced Synthesis \u0026amp; Catalysis》2016,358(21):3355-3361
N‐Propargyl‐ and N‐homoallenyl‐2‐bromo‐β‐tryptamines undergo gold(I)‐catalyzed dearomatizing cyclizations to afford 2‐bromospiroindolenines that are in situ hydrolyzed to furnish spirooxindoles in a one‐pot process. Tryptophane derivatives (R2=CO2Et) led upon cyclization to chiral spirooxindoles in excellent diastereoselectivities.
11.
Copper‐Catalyzed Addition of Alkylboranes to Iminoacetates: Access to α‐Alkyl Branched α‐Amino Acids
Xinsheng Xiao Wei Zhang Xiaoxia Lu Yuanfu Deng Huangfeng Jiang Wei Zeng 《Advanced Synthesis \u0026amp; Catalysis》2016,358(15):2497-2509
A copper(I)‐catalyzed addition of alkylborane reagents to α‐iminoacetates has been developed to assemble both acyclic and cyclic α‐branched α‐amino carboxylic acid derivatives in good yields. A wide variety of unactivated alkenes are well tolerated in this transformation.
12.
Pankaj Chauhan Suruchi Mahajan Uur Kaya Arto Valkonen Kari Rissanen Dieter Enders 《Advanced Synthesis \u0026amp; Catalysis》2016,358(20):3173-3178
An efficient asymmetric synthesis of spirocyclohexenone β‐lactams bearing three contiguous stereocenters has been achieved in moderate to good yields and high stereoselectivities. The protocol involves the combination of a squaramide‐catalyzed sulfa‐Michael addition under desymmetrization via a dynamic kinetic resolution of racemic 2,5‐cyclohexadienones.
13.
Danila Gasperini Lorenzo Maggi Stphanie Dupuy Richard M. P. Veenboer David B. Cordes Alexandra M. Z. Slawin Steven P. Nolan 《Advanced Synthesis \u0026amp; Catalysis》2016,358(23):3857-3862
The improved synthesis of γ‐, δ‐ and ϵ‐lactones using a dinuclear N‐heterocyclic carbene (NHC)‐gold(I) catalyst is reported. This solvent‐free process provides access to γ‐ and δ‐lactones in high regio‐ and stereoselectivity. Reactions were performed at low catalyst loadings and without the need for any additives. The use of a digold pre‐catalyst provides a new synthetic route to functionalised ϵ‐lactones, poorly accessible using previous methodologies.
14.
This report focuses on the utilization of N‐acylimines in addition reactions aimed at the preparation of heterocyclic compounds. These can be directly obtained by reaction of N‐acylimines with suitable nucleophilic reagents or prepared by further elaboration of the initially formed adducts. The asymmetric synthesis of these hetero‐ and polyheterocyclic derivatives is mostly achieved using chiral catalyzed reactions, including the recently introduced enantioselective Biginelli reaction. Applications of isatin ketimines to the stereoselective preparation of biologically active spiroxindole compounds are also reported.
15.
Jimil George Hun Young Kim Kyungsoo Oh 《Advanced Synthesis \u0026amp; Catalysis》2016,358(23):3714-3718
The direct regioselective synthesis of highly functionalized pyrroles with two different electron‐withdrawing groups has been developed using an angle strain‐induced 1,2‐shift of an electron‐withdrawing group in 2H‐pyrroles. The preferential migration aptitude of an electron‐withdrawing group over alkyl and aryl groups is believed to be the result of the orbital overlap between the internal alkene and the electron‐withdrawing group. The newly developed regioselective synthesis of pyrroles features a wide substrate scope, simple reaction set‐up, and high yields (60–82%), capturing the essence of alkyne‐isocyanide “click” reactions.
16.
Nai‐Kai Li Ling‐Pei Kong Zheng‐Hang Qi Shao‐Jie Yin Jun‐Qi Zhang Bing Wu Xing‐Wang Wang 《Advanced Synthesis \u0026amp; Catalysis》2016,358(19):3100-3112
Several chiral BINOL‐derived bisoxazoline (BOX)/copper(II) complexes were synthesized and evaluated as catalysts for the Friedel–Crafts reaction of indoles with isatin‐derived β,γ‐unsaturated α‐keto esters. The resulting bis‐indole products bearing a quaternary stereocenter were obtained in excellent yields and enantioselectivities. Additionally, the desired products were practically transformed to α‐amino esters, α‐hydroxy esters and α‐keto amides. It is noteworthy that this catalytic procedure was conducted with a catalyst loading of 0.5 mol% without any discernible decrease in the reactivity or enantioselectivity.
17.
Rengwei Sun Wei Song Chunmei Ma Huiwen Zhang Xinhong Yu 《Advanced Synthesis \u0026amp; Catalysis》2016,358(24):3977-3982
A direct access to multisubstituted 1,3‐dienes by α‐exclusive alkylidenation of crotonic derivatives has been developed. This protocol, mediated by titanium tetrachloride chelation, features excellent regio‐ and stereoselectivity, mild reaction conditions, easy operation and wide substrate scope. Conversions of the derived dienes to other useful molecules were also explored.
18.
Fuzhao Xue Xiaoze Bao Liwei Zou Jingping Qu Baomin Wang 《Advanced Synthesis \u0026amp; Catalysis》2016,358(24):3971-3976
A natural quinine‐catalyzed, efficient and practical asymmetric α‐hydroxylation of 4‐substituted pyrazolones has been developed, delivering a broad spectrum of pyrazolones bearing an oxygen‐attached carbon stereocenter at C‐4 in high yields and excellent enantioselectivities. The broad substrate scope, ready availability of the catalyst, ease of operation, and valuable transformation of the product highlight the practical utility of this process.
19.
Siva Senthil Kumar Boominathan Ruei‐Jhih Hou Wan‐Ping Hu Po‐Jui Huang Jeh‐Jeng Wang 《Advanced Synthesis \u0026amp; Catalysis》2016,358(18):2984-2989
A palladium‐catalyzed domino strategy has been developed for the synthesis of 2,3‐disubstituted benzofuran derivatives. This cascade reaction sequence involves intermolecular carbopalladation and C(sp3)−H functionalization followed by isomerization.
20.
Guangchen Li Guangshuai Zhou Daisy Zhang‐Negrerie Yunfei Du Jianhui Huang Kang Zhao 《Advanced Synthesis \u0026amp; Catalysis》2016,358(22):3534-3540
A domino reaction of palladium(II)‐catalyzed dual C–H functionalization with subsequent intramolecular annulation is presented. This method provides a convenient synthesis of a range of symmetrical and unsymmetrical biologically important (E)‐bisindole‐2‐ones under extremely mild reaction conditions – room temperature, green oxidant and no additive. The reaction mechanism is elucidated in light of the yield values as well as additional control experiment results.