885595-01-7Relevant academic research and scientific papers
C-H Alkylation of Aldehydes by Merging TBADT Hydrogen Atom Transfer with Nickel Catalysis
Murugesan, Vetrivelan,Ganguly, Anirban,Karthika, Ardra,Rasappan, Ramesh
, p. 5389 - 5393 (2021/07/21)
Catalyst controlled site-selective C-H functionalization is a challenging but powerful tool in organic synthesis. Polarity-matched and sterically controlled hydrogen atom transfer (HAT) provides an excellent opportunity for site-selective functionalization. As such, the dual Ni/photoredox system was successfully employed to generate acyl radicals from aldehydes via selective formyl C-H activation and subsequently cross-coupled to generate ketones, a ubiquitous structural motif present in the vast majority of natural and bioactive molecules. However, only a handful of examples that are constrained to the use of aryl halides are developed. Given the wide availability of amines, we developed a cross-coupling reaction via C-N bond cleavage using the economic nickel and TBADT catalyst for the first time. A range of alkyl and aryl aldehydes were cross-coupled with benzylic and allylic pyridinium salts to afford ketones with a broad spectrum of functional group tolerance. High regioselectivity toward formyl C-H bonds even in the presence of α-methylene carbonyl or α-amino/oxy methylene was obtained.
Light-Driven Carbene Catalysis for the Synthesis of Aliphatic and α-Amino Ketones
Bay, Anna V.,Cheong, Paul Ha-Yeon,Farah, Abdikani Omar,Fitzpatrick, Keegan P.,González-Montiel, Gisela A.,Scheidt, Karl A.
supporting information, p. 17925 - 17931 (2021/07/17)
Single-electron N-heterocyclic carbene (NHC) catalysis has gained attention recently for the synthesis of C?C bonds. Guided by density functional theory and mechanistic analyses, we report the light-driven synthesis of aliphatic and α-amino ketones using single-electron NHC operators. Computational and experimental results reveal that the reactivity of the key radical intermediate is substrate-dependent and can be modulated through steric and electronic parameters of the NHC. Catalyst potential is harnessed in the visible-light driven generation of an acyl azolium radical species that undergoes selective coupling with various radical partners to afford diverse ketone products. This methodology is showcased in the direct late-stage functionalization of amino acids and pharmaceutical compounds, highlighting the utility of single-electron NHC operators.
Combined Photoredox and Carbene Catalysis for the Synthesis of Ketones from Carboxylic Acids
Betori, Rick C.,Davies, Anna V.,Fitzpatrick, Keegan P.,Scheidt, Karl A.
supporting information, p. 9143 - 9148 (2020/03/30)
As a key element in the construction of complex organic scaffolds, the formation of C?C bonds remains a challenge in the field of synthetic organic chemistry. Recent advancements in single-electron chemistry have enabled new methods for the formation of various C?C bonds. Disclosed herein is the development of a novel single-electron reduction of acyl azoliums for the formation of ketones from carboxylic acids. Facile construction of the acyl azolium in situ followed by a radical–radical coupling was made possible merging N-heterocyclic carbene (NHC) and photoredox catalysis. The utility of this protocol in synthesis was showcased in the late-stage functionalization of a variety of pharmaceutical compounds. Preliminary investigations using chiral NHCs demonstrate that enantioselectivity can be achieved, showcasing the advantages of this protocol over alternative methodologies.
PHARMACEUTICAL COMPOUNDS
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, (2008/06/13)
The invention provides a compound having the formula (I): or salts, solvates, tautomers or N-oxides thereof, wherein T is N or CR5; J1-J2 is N=C(R6), (R7)C=N, (R8)N-C(O), (R8)2C-C(O), N=N or (R7)C=C(R6); A is an optionally substituted saturated C1-7 hydrocarbon linker group having a maximum chain length of 5 atoms extending between R1 and NR2R3 and a maximum chain length of 4 atoms extending between E and NR2R3, one of the carbon atoms in the linker group being optionally replaced by oxygen or nitrogen; E is a monocyclic or bicyclic carbocyclic or heterocyclic group or an acyclic group X-G wherein X is CH2, O, S or NH and G is a C1-4 alkylene chain wherein one of the carbon atoms is optionally replaced by O, S or NH; R1 is hydrogen or an aryl or heteroaryl group; R2 and R3 are each hydrogen, optionally substituted C1-4 hydrocarbyl or optionally substituted C1-4 acyl; or NR2R3 forms an imidazole group or a saturated monocyclic heterocyclic group having 4-7 ring members; or NR2R3 and A together form a saturated monocyclic heterocyclic group having 4-7 ring members which is optionally substituted by C1-4 alkyl; or NR2R3 and the adjacent carbon atom of linker group A together form a cyano group; or R1, A and NR2R3 together form a cyano group; and R4, R5, R6, R7 and R8 are each independently selected from hydrogen and various substituents as defined in the claims, wherein the compound is for use in: (a) the treatment or prophylaxis of a disease or condition in which the modulation (e.g. inhibition) of ROCK kinase or protein kinase p70S6K is indicated; and/or (b) the treatment of a subject or patient population in which the modulation (e.g. inhibition) of ROCK kinase or protein kinase p70S6K is indicated.
ORTHO- CONDENSED PYRIDINE AND PYRIMIDINE DERIVATIVES (E. G. PURINES) AS PROTEIN KINASES INHIBITORS
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Page/Page column 129, (2008/06/13)
The invention provides a compound for use in the prophylaxis or treatment of a disease state or condition mediated by protein kinase B, the compound having the formula (I): or salts, solvates, tautomers or N-oxides thereof, wherein T is N or CR5; J1-J2 is N=C(R6), (R7)C=N, (R8)N-C(O), (R8)2C-C(O), N=N or (R7)C=C(R6); A is an optionally substituted saturated C1-7 hydrocarbon linker group having a maximum chain length of 5 atoms extending between R1 and NR2R3 and a maximum chain length of 4 atoms extending between E and NR2R3, one of the carbon atoms in the linker group being optionally replaced by oxygen or nitrogen; E is a monocyclic or bicyclic carbocyclic or heterocyclic group or an acyclic group X-G wherein X is CH2, O, S or NH and G is a C1-4 alkylene chain wherein one of the carbon atoms is optionally replaced by O, S or NH; R1 is hydrogen or an aryl or heteroaryl group; R2 and R3 are each hydrogen, optionally substituted C1-4 hydrocarbyl or optionally substituted C1-4 acyl; or NR2R3 forms an imidazole group or a saturated monocyclic heterocyclic group having 4-7 ring members; or NR2R3 and A together form a saturated monocyclic heterocyclic group having 4-7 ring members which is optionally substituted by C1-4alkyl; or NR2R3 and the adjacent carbon atom of linker group A together form a cyano group; or R1, A and NR2R3 together form a cyano group; and R4, R5, R6, R7 and R8 are each independently selected from hydrogen and various substituents as defined in the claims.
