Article
Chemistry, Applied
Deyuan Meng, Jing He, Woojin Yoon, Hoseop Yun, Jung Tae Han, Jaesook Yun
Summary: In this study, the catalytic 1,6-addition of chiral alkyl copper nucleophiles generated from borylalkenes and a copper-hydride catalyst was successfully conducted under mild conditions. The controlled chemo- and stereoselectivity played a crucial role in the reductive coupling process, resulting in efficient synthesis of asymmetric 1,6-adducts of p-quinone methides through multicomponent and catalytic tandem reactions.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Organic
Guangmiao Wu, Tao Li, Fuhai Liu, Yulong Zhao, Shiqiang Ma, Shouchu Tang, Xingang Xie, Xuegong She
Summary: An efficient thiourea-catalyzed 1,6-conjugate addition of indoles to para-quinone methides (p-QMs) was developed, where p-QMs were activated by a weak hydrogen-bond effect. The reaction features mild conditions and a wide substrate scope, allowing for the synthesis of a series of C-3 bisaryl methine substituted indoles in high yield.
TETRAHEDRON LETTERS
(2021)
Article
Chemistry, Organic
Kavyashree Kuppayya Gond, Mahagundappa Rachappa Maddani
Summary: In this study, isochroman-1,4-diones and addition products were selectively synthesized through KOBu-Catalyzed addition of sulfonylphthalides to p-quinone methides. It is noteworthy that isochroman-1,4-diones were obtained via an unprecedented oxidative annulation pathway. The research highlights the broad substrate scope, high yields, shorter reaction time, and mild reaction conditions. Furthermore, some addition products can be transformed into functionalized heterocyclic molecules. Additionally, the scalability experiment demonstrates the practical feasibility of preparing isochroman-1,4-diones in larger scale reactions.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Applied
Yuan Chen, Rui Yu, Min Wang, Yanmin Huang, Yungui Peng
Summary: An asymmetric 1,6-conjugate addition reaction of dialkyl diazomethylphosphonates to para-quinone methides was developed using phase-transfer catalysis, yielding chiral diarylmethylated diazomethylphosphonates with high yields and enantioselectivities. The resulting products were further transformed into bioactive compounds with diarylmethine stereogenic centers.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Organic
Jing He, Deyuan Meng, Dong Yeon Lee, Jaesook Yun
Summary: We report a ligand-free copper-catalyzed 1,6-addition reaction of alpha-borylalkyl copper species with para-quinone methides. The reaction, catalytically generated from gem-diborylalkanes, shows good yield for various para-quinone methides and substituted gem-diborylalkanes with a catalytic amount of CuI. This catalytic system provides a cost-effective process with good functional group tolerance under mild conditions.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Lei Xie, Xuyang Zang, Wanxing Liu, Ping Wu, Zhaoxue Wang, Chenyi Zhao, Zhenzhen Gao, Xiaojing Li, Shaozhen Nie, Lingang Wu
Summary: An efficient method for the synthesis of a variety of large diarylmethane thioether derivatives is developed through catalyst-free 1,6-conjugate addition. The reaction yields high to excellent results, and the system is also suitable for other sulfur-based nucleophiles. The resulting products can be readily converted into other valuable diarylmethane derivatives.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Zhiguang Zhang, Xiaoyu Tan, Ao Sui, Bingzhu Zhang, Yong Zhang
Summary: A DBU-catalyzed 1,6-addition reaction of quinazolinones and quinolones with para-quinone methides under mild conditions is reported. Diarylmethane compounds functionalized with quinazolinones and quinolones were obtained in good yields (41-95%) with DBU as catalyst.
TETRAHEDRON LETTERS
(2022)
Article
Chemistry, Organic
Chada Raji Reddy, Ankita Kumari, Suraj Aswale, Amol D. Patil, Y. Lakshmi Prapurna
Summary: The reaction of alkynyl p-quinone methide (pQM) with keto-methylenes through a base-mediated tandem 1,6-addition/annulation sequence, [2 + 3] annulation, affords furans for the first time. Various functionalized furans, including fused derivatives, can be obtained in good to excellent yields under mild reaction conditions. The effectiveness of alkynyl pQMs is demonstrated by their ability to access isoxazoles, pyrazoles via [3 + 2] annulation, and pyridines through [3 + 3] annulation in the presence of different bis-nucleophiles.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Xinyuan Liu, Binbin Liu, Zhan Shi, Chen Tan, Rong Fan, Zhi Li, Jiajing Tan
Summary: A carbon-carbon bond formation reaction catalyzed by Hf(OTf)(4) between 2-alkyl-azaarenes and para-quinone methides (p-QMs) was reported, providing rapid access to a variety of triarylethane products in good yields. The catalyst loading could be reduced to 1 mol%. Studies on scale-up reactions and product derivatization were also presented.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Xin Li, Songtao He, Qiuling Song
Summary: A newly designed strategy is presented in this study, which rapidly introduces ethyl difluoroacetate radicals through a dialkylzincs induced radical 1,6-conjugate addition pathway. This protocol achieves high yields and excellent functional group compatibility, allowing the incorporation of a gem-difluoromethylene motif within minutes.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Organic
Xin Li, Guoliang Gao, Songtao He, Qiuling Song
Summary: The article presents the first 1,6-conjugate addition of diborylmethane using a simple and inexpensive copper catalytic system. This method demonstrates high yields, good selectivities, and compatibility with a wide range of functional groups.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Organic
Ferruh Lafzi
Summary: This article presents a metal and additive-free method using acetic acid as a catalyst for the C3-alkylation of indolizines with para-Quinone Methides. The method allows for the synthesis of various substituted indolizine derivatives with good functional group tolerance and high yields (up to 93%). The gram-scale synthesis and product derivatization demonstrate the synthetic potential of this technique.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Ramesh A. Gaikwad, Sumit B. Kamble, Suresh B. Waghmode
Summary: A novel one-pot method for synthesizing spiro 1,4-dioxane cyclohexadienone derivatives has been developed using a transition metal-free and Bronsted acid mediated 1,6-conjugate addition and ipso cyclization reaction. This method demonstrates broad substrate scope and high functional group tolerance, achieving high yields of the desired spirocyclic scaffolds.
CHEMISTRY-AN ASIAN JOURNAL
(2022)
Article
Chemistry, Organic
Ana Julia S. Senna, Manoel T. Rodrigues Jr, Hugo Santos, Lucas A. Zeoly, Ralph C. Gomes, Fernando Coelho
Summary: A 1,6-addition reaction of indolizines to para-quinone methides with only 2 mol% indium chloride as a catalyst was developed. The method achieves regioselective addition of indolizines at positions 1 and/or 3 to p-quinone methides, leading to high yields of the desired products (up to 99%) under mild conditions and short reaction time.
TETRAHEDRON LETTERS
(2023)
Article
Chemistry, Organic
Han-Peng Pan, Zhi-Qiang Zhu, Zong-Wang Qiu, Hong-Fu Liu, Jiong-Dong Ma, Bao Qiong Li, Na Feng, Ai-Jun Ma, Jin-Bao Peng, Xiang-Zhi Zhang
Summary: This study presents an efficient method for dearomatization of 2,3-disubstituted indoles to access diverse indolimines with quaternary carbon centers and tetrasubstituted allenes through 1,8-addition of (aza)-para-quinone methides. The products can be obtained in good yields (up to 99%) with separability of isomers, diversified product transformations, and easy scale-up potential, showcasing the method's applicability.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
