1198575-45-9Relevant academic research and scientific papers
Cp*Co(III) catalyzed annulation of N-Cbz hydrazones for the redox-neutral synthesis of isoquinolines via C–H/N–N bond activation
Subhedar, Dnyaneshwar D.,Deshmukh, Dewal S.,Bhanage, Bhalchandra M.
, p. 3121 - 3130 (2019)
A new cascade oxidative cyclization reaction of N-Cbz hydrazones with internal alkynes has been explored for the preparation of isoquinoline derivatives using Cp*CoIII-catalyst through C–H and N–N bond functionalization. N-Cbz hydrazones are ra
N-Tosylhydrazone as an oxidizing directing group for the redox-neutral access to isoquinolines via Cp?Co(III)-Catalyzed C–H/N–N activation
Deshmukh, Dewal S.,Gangwar, Neha,Bhanage, Bhalchandra M.
, (2021/06/28)
Herein, an efficient and economic access has been revealed for the synthesis of isoquinolines via C–H bond activation strategy by using comparatively inexpensive and versatile cobalt catalyst. A hardly investigated directing group, N-tosylhydrazone has been effectively applied as an internal oxidant for an annulation reaction with internal alkynes via C–H/N–N bond functionalization. This catalytic protocol works for the extensive variety of substrates in moderate to excellent yields under external oxidant-free conditions. Additionally, the proposed protocol has advantages such as broad substrate coverage with significant product yields, readily synthesized substrates as well as scalability up to the gram quantity which further improves the competency of the methodology.
Rhodium-Catalyzed One-Pot Access to N-Polycyclic Aromatic Hydrocarbons from Aryl Ketones through Triple C-H Bond Activations
Biswal, Pragati,Banjare, Shyam Kumar,Pati, Bedadyuti Vedvyas,Mohanty, Smruti Ranjan,Ravikumar, Ponneri Chandrababu
, p. 1108 - 1117 (2021/01/09)
A Rh-catalyzed pot and step economic synthesis of aza-polycyclic aromatic hydrocarbons (N-PAHs) from readily available aryl ketones and alkynes has been disclosed. Additionally, a novel synthetic application of the well-known aminating reagent hydroxylamine-O-sulfonic acid (HOSA) has been explored as an in situ redox-neutral directing group for the formation of N-PAHs via isoquinoline. Multiple bond formation in a single operation through a cascade of triple C-H bond activations is the beauty of this protocol. The challenging annulations of two different alkynes in a regioselective fashion have been demonstrated effectively. Mechanistic studies reveal that 3,4-diphenyl-1-methylisoquinoline is an active intermediate for this one-pot transformation.
Rh(III)?catalyzed synthesis of isoquinolines from N-hydroxyoximes and alkynes in γ-valerolactone
Jiang, Kuan-Chang,Wang, Liang,Chen, Qun,He, Ming-Yang,Shen, Ming-Gui,Zhang, Zhi-Hui
supporting information, p. 94 - 102 (2020/09/21)
A Rh (III)?catalyzed synthesis of isoquinoline derivatives from N-hydroxyoximes and alkynes via C–H activation/annulation process in biomass-derived γ-valerolactone (GVL) has been developed. A series of functional groups were well tolerated, affording the desired products in good to excellent yields.
Hydroxylamine-O-Sulfonic Acid (HOSA) as a Redox-Neutral Directing Group: Rhodium Catalyzed, Additive Free, One-Pot Synthesis of Isoquinolines from Arylketones
Biswal, Pragati,Pati, Bedadyuti Vedvyas,Chebolu, Rajesh,Ghosh, Asit,Ravikumar
, p. 1006 - 1014 (2020/02/15)
A new application of hydroxylamine-O-sulfonic acid (HOSA) has been discovered whereby aromatic ketones react with HOSA and alkynes to form isoquinolines in the presence of a RhIII catalyst. This C–H/N–O annulation methodology gives excellent yields even without any silver additive, acid/base or metal oxidant. This is the first report wherein a directing group is simultaneously forming in situ, acting as acid additive, and also as an internal oxidant.
Ruthenium-Catalyzed Annulation of N -Cbz Hydrazones via C-H/N-N Bond Activation for the Rapid Synthesis of Isoquinolines
Bhanage, Bhalchandra M.,Deshmukh, Dewal S.
, p. 2506 - 2514 (2019/06/08)
In this work, N -Cbz hydrazone has been employed as a rarely explored directing group for the synthesis of isoquinolines by annulation with internal alkynes via C-H/N-N activation using Ru catalyst. Additive as well as external oxidant-free rapid protocol
Rapid and Atom Economic Synthesis of Isoquinolines and Isoquinolinones by C–H/N–N Activation Using a Homogeneous Recyclable Ruthenium Catalyst in PEG Media
Deshmukh, Dewal S.,Gangwar, Neha,Bhanage, Bhalchandra M.
, p. 2919 - 2927 (2019/05/10)
Herein, we report an atom-efficient, rapid, green, and sustainable approach to synthesize isoquinolines and isoquinolinones using a homogeneous recyclable ruthenium catalyst in PEG Media assisted by microwave energy. Dibenzoylhydrazine was used for C–H/N–N activation reactions for the first time in combination with ketazine as oxidizing directing groups for annulation reactions with internal alkynes. The developed protocol is environmentally benign due to significantly shortened times with an easy extraction method, higher atom economy, external oxidant and silver or antimony salt free conditions, applicability to a gram scale synthesis, use of biodegradable solvent and wide substrate scope with higher product yields. Moreover, it is worth noting that the established methodology allowed reuse of the catalytic system for up to five successive runs with minimal loss in activity.
Cp*Co(iii)-catalyzed annulation of azines by C-H/N-N bond activation for the synthesis of isoquinolines
Deshmukh, Dewal S.,Yadav, Prashant A.,Bhanage, Bhalchandra M.
, p. 3489 - 3496 (2019/04/14)
Herein, an efficient, atom economic and external oxidant free approach has been disclosed for the synthesis of isoquinolines. Azines were employed for annulation reactions with alkynes via sequential C-H/N-N bond activation using an air-stable cobalt catalyst. The method takes advantage of the incorporation of both the nitrogen atoms of azines into the desired isoquinoline products, offering the highest atom economy. In addition, the developed protocol works under external oxidant as well as silver salt free conditions. Furthermore, the established methodology features a relatively broad substrate scope with high product yields and scalability up to the gram level.
Easy access to synthesize isoquinolines from aryl ketoximes and internal alkynes via Iridium (III)-catalyzed C[sbnd]H/N[sbnd]O bond activation
Lin, Wei,Hu, Xiu-Xiu,Zhuang, Cang-Wei,Wang, Ya-Zhen
, p. 3015 - 3023 (2019/04/30)
A highly efficient approach to synthesize isoquinoline derivatives through Iridium(III)-catalyzed cyclization of aryl ketoximes and internal alkynes without oxidant is reported. A broad range isoquinolines are obtained in good to excellent yields and various functional groups are well tolerated.
Cp?-Free Cobalt-Catalyzed C-H Activation/Annulations by Traceless N, O-Bidentate Directing Group: Access to Isoquinolines
Li, Xiao-Cai,Du, Cong,Zhang, He,Niu, Jun-Long,Song, Mao-Ping
, p. 2863 - 2866 (2019/04/17)
N,O-Bidentate directing-enabled, traceless heterocycle synthesis is described via Cp?-free cobalt-catalyzed C-H activation/annulation. The weakly coordinating nature of the carboxylic acid was employed for the preparation of isoquinolines. Meanwhile, the N-O bond of the α-imino-oxy acid can serve as an internal oxidant. Terminal as well as internal alkynes can be efficiently applied to the catalytic system. This operationally simple approach shows a broad substrate scope with the products obtained in good to excellent yields.
