79756-91-5Relevant academic research and scientific papers
Hydrazine Hydrate Accelerates Neocuproine–Copper Complex Generation and Utilization in Alkyne Reduction, a Significant Supplement Method for Catalytic Hydrogenation
Chen, Guoliang,He, Xiaoyan,Huang, Gang,Lu, Xiuhong,Wang, Jincheng,Yang, Zhenjiao,Zhang, Yongsheng,Zhang, Zeng
, p. 17696 - 17709 (2021/12/09)
Diimine (HN═NH) is a strong reducing agent, but the efficiency of diimine oxidized from hydrazine hydrate or its derivatives is still not good enough. Herein, we report an in situ neocuproine–copper complex formation method. The redox potential of this complex enable it can serve as an ideal redox catalyst in the synthesis of diimine by oxidation of hydrazine hydrate, and we successfully applied this technique in the reduction of alkynes. This reduction method displays a broad functional group tolerance and substrate adaptability as well as the advantages of safety and high efficiency. Especially, nitro, benzyl, boc, and sulfur containing alkynes can be reduced to the corresponding alkanes directly, which provides a useful complementary method to traditional catalytic hydrogenation. Besides, we applied this method in the preparation of the Alzheimer’s disease drug CT-1812 and studied the mechanism.
Ru(ii)-catalyzed allenylation and sequential annulation of: N -tosylbenzamides with propargyl alcohols
Kumar, Shreemoyee,Nair, Akshay M.,Volla, Chandra M. R.
supporting information, p. 6280 - 6283 (2021/07/02)
We hereby report Ru(ii)-catalyzed C(sp2)-H allenylation of N-tosylbenzamides to access multi-substituted allenylamides. Furthermore, the allenylamides were converted to the corresponding isoquinolone derivatives via base mediated annulation. The current protocol features low catalyst loading, mild reaction conditions, high functional group compatibility and desired scalability. The unique functionality of the afforded allenes allowed further transformations to expand the practicality of the protocol. This journal is
Rhodium-Catalyzed Annulation of Phenacyl Ammonium Salts with Propargylic Alcohols via a Sequential Dual C-H and a C-C Bond Activation: Modular Entry to Diverse Isochromenones
Nanubolu, Jagadeesh Babu,Reddy Singam, Maneesh Kumar,Sridhar Reddy, Maddi,Suresh, Vavilapalli,Suri Babu, Undamatla
supporting information, p. 7888 - 7893 (2021/10/25)
Given their omnipresence in natural products and pharmaceuticals, isochromenone congeners are one of the most privileged scaffolds to synthetic chemists. Disclosed herein is a dual (ortho/meta) C-H and C-C activation of phenacyl ammonium salts (acylammonium as traceless directing group) toward annulation with propargylic alcohols to accomplish rapid access for novel isochromenones by means of rhodium catalysis from readily available starting materials. This operationally simple protocol features broad substrate scope and wide functional group tolerance. Importantly, the protocol circumvents the need of any stoichiometric metal oxidants and proceeds under aerobic conditions.
Rhodium-catalyzed oxidative coupling of benzoic acids with propargyl alcohols: An efficient access to isocoumarins
Luo, Feihua,He, Shuhua,Gou, Quan,Chen, Jinyang,Zhang, mingzhong
supporting information, (2020/12/29)
An efficient protocol of Rh(III)-catalyzed oxidative cyclization of benzoic acids with propargyl alcohols to give substituted isocoumarins under mild conditions was reported. A variety of substrates were applied in this reaction in yields up to 89%.
Bimetal Cooperatively Catalyzed Arylalkynylation of Alkynylsilanes
Chen, Xing,Li, Mengke,Liu, Zhipeng,Yang, Can,Xie, Haisheng,Hu, Xinwei,Su, Shi-Jian,Jiang, Huanfeng,Zeng, Wei
supporting information, p. 6724 - 6728 (2021/09/08)
An unprecedented Pd/Rh cooperatively catalyzed arylalkynylation of alkynylsilanes was developed to merge an alkynylidene moiety with benzosilacycle. These silaarenes possess a particular aggregation-induced emission behavior. Mechanistic investigations demonstrate that the relay trimetallic transmetalation plays a pivotal role in governing this transformation.
Utilizing a copper-free Sonogashira reaction in the synthesis of the leukotriene a4 hydrolase modulator batatasin IV
Petruncio, Greg,Girgis, Michael,Moummi, Sanae,Jayatilake, Meth,Lee, Kyung Hyeon,Paige, Mikell
supporting information, (2020/10/27)
Batatasin IV is a dihydrostilbenoid isolated from Chinese yams which was shown to have inhibitory activities against plant growth. Later studies showed that this compound may exhibit anti-inflammatory properties by inhibiting the epoxide hydrolase activity of the leukotriene A4 hydrolase enzyme. To access the dihydrostilbenoid skeleton, a copper-free SPhos-mediated Sonogashira reaction was conceived and the substrate scope was explored. Our results indicate that the reaction can tolerate the presence of free alcohols, aldehydes, nitro groups, and anilinyl groups. However, a substituent with an acidic phenol or carboxylic acid group gave significantly lower yields. Next, a total synthesis of batatasin IV was accomplished in 16% overall yield incorporating the reported copper-free Sonogashira reaction. Finally, we show that batatasin IV inhibits the hydrolysis of alanine p-nitroanilide by leukotriene A4 hydrolase with an IC50 of 91.4 μM.
Visible-light-driven selective alkenyl C-P bond cleavage of allenylphosphine oxides
Wei, Kai,Luo, Kai,Liu, Fang,Wu, Lei,Wu, Li-Zhu
supporting information, p. 1994 - 1998 (2019/03/29)
An efficient method for highly selective alkenyl C-P bond cleavage, enabled by organic dyes and visible-light irradiation, was developed. This novel protocol involves a highly regioselective radical pathway initiated by singlet oxygen, affording diverse a
Palladium(II)/Lewis acid cocatalyzed oxidative annulation of 2-alkenylanilines and propargylic esters: An access to benzo[ b]azepines
Qiao, Hong,Zhang, Shengjun,Li, Kangkang,Cao, Zhengqiang,Zeng, Fanlong
, p. 10843 - 10851 (2019/09/12)
An attractive approach to valuable yet synthetically challenging benzo[b]azepines was established via palladium(II)/Lewis acid cocatalyzed oxidative [5 + 2] annulation of readily available 2-alkenylanilines and propargylic esters. The protocol features mild reaction conditions and good functional group tolerance, constituting an array of benzo[b]azepines in yields of 30-75%.
Rhodium-Catalyzed Highly Regio- and Enantioselective Hydrogenation of Tetrasubstituted Allenyl Sulfones: An Efficient Access to Chiral Allylic Sulfones
Long, Jiao,Shi, Liyang,Li, Xiong,Lv, Hui,Zhang, Xumu
supporting information, p. 13248 - 13251 (2018/09/21)
A highly regio- and enantioselective hydrogenation of challenging tetrasubstituted allenyl sulfones has been developed, affording chiral allylic sulfones in good yields with excellent regio- and enantioselectivities (up to 99 % yield and 99 % ee). This me
Cleavage of C–C and C–O Bonds to Form C–C Bonds: Direct Cross-Coupling between Acetylenic Alcohols and Benzylic Carbonates
Mi, Zhiyuan,Tang, Jiahao,Guan, Zhipeng,Shi, Wei,Chen, Hao
supporting information, p. 4479 - 4482 (2018/09/10)
A palladium-catalyzed cross-coupling reaction between C(sp) and C(sp3) centers was achieved in excellent yields via C–C bond cleavage and C–O bond cleavage. This procedure uses relatively stable acetylenic alcohols as reactants instead of unsta
