64433-61-0Relevant academic research and scientific papers
Carbene-catalyzed aerobic oxidation of isoquinolinium salts: Efficient synthesis of isoquinolinones
Wang, Guanjie,Hu, Wanyao,Hu, Zhouli,Zhang, Yuxia,Yao, Wei,Li, Lin,Fu, Zhenqian,Huang, Wei
supporting information, p. 3302 - 3307 (2018/07/29)
A mild and environmentally friendly carbene-catalyzed aerobic oxidation of isoquinolinium salts was successfully realized. Accordingly, a diverse set of isoquinolinones and phenanthridinones was efficiently prepared in good to excellent yields. The mechanistic study indicates that the formation of an aza-Breslow intermediate is the crucial step in this transformation. This reaction features ambient air as the sole oxidant and oxygen source, a broad substrate scope, and excellent functional-group tolerance and proceeds under mild reaction conditions. Furthermore, a highly efficient synthesis of bioactive molecules and natural products including N-methylcrinasiadine, N-isopentylcrinasiadine, N-phenethylcrinasiadine, isoindolo[2,1-b]isoquinolin-5(7H)-one, PJ-34, rac-Gusanlung D, rosettacin, 8-oxopseudopalmatine and ilicifoline B was accomplished.
Copper-Catalyzed Annulation: A Method for the Systematic Synthesis of Phenanthridinium Bromide
Jhang, Yuan-Ye,Fan-Chiang, Tai-Ting,Huang, Jun-Min,Hsieh, Jen-Chieh
, p. 1154 - 1157 (2016/03/15)
A novel procedure for the Cu-catalyzed systematic synthesis of phenanthridinium bromide is reported. This transformation was achieved with direct construction of central pyridinium core by using an in situ formed biaryl imine as a substrate. Tolerance of a very wide variety of N-substituents is indicated; this has never previously been disclosed by other reports. Application of this method to synthesis of the natural alkaloid bicolorine, and its derivatives, was also carried out in only three synthetic steps from commercially available compounds.
Marcus Theory of Hydride Transfer from an Anionic reduced Deazaflavin to NAD+ Analogues
Lee, In-Sook Han,Ostovic, Drazen,Kreevoy, Maurice
, p. 3989 - 3993 (2007/10/02)
Eighteen rate constants, kij for hydride transfer from the conjugate base of 1,5-dihydro-3,10-dimethyl-5-diazaisoalloxazine to a variety of pyridinium, quinolinium, phenanthridinium, and acridinium ions have been determined. (All the oxidizing agents can be regarded as analogues of NAD+.) The kij values span 7 powers of 10 and the corresponding equilibrium constants, Kij, span more than 13 powers of 10.For reactions with ΔG0 near zero, the kij values are close to those given by modified Marcus theory (ref 10).However, with more negative ΔG0 values, the observed kij increase more strogly than the calculated values.Agreement can be produced by making the standard free energy of precursor complex formation, symbolized WT +- here, to indicate that it applies to reactants of opposite charge, a linear function of ΔG0, and treating the slope and interrcept of the linear relation as adjustable parameters.The best fit is obtained with WT+-(in kJ*mol-1)=-9.4+0.11ΔG0.An avarage discrepancy between calculated and observed ln kij values of 0.5 is achieved, which is a good as the overall fit achieved for hydride transfer from neutral NADH analogues to NAD+ analogues (ref 10).The form and the parameterization of Wf are shown to be a physically reasonable approximation for reactions with ΔG00.These results strengthen the conclusion (ref 10) that a wide range of hydride transfer rates can be quantitavely understood without introducing high-energy metastable intermediates (radicals and radical ions).
Isotope Effects on Hydride Transfer between NAD+ Analogues
Ostovic, Drazen,Roberts, Roger M. G.,Kreevoy, Mourice M.
, p. 7629 - 7631 (2007/10/02)
Primary kinetic hydrogen isotope effects (KIE's) for hydride transfer between NAD+ analogues are between 6 and 4, for reactions with equilibrium constants ranging from 0.7 to 1016.There is no sign of the sharp change in KIE which would signal the change of a rate-limiting step in a multistep mechanism, and other evidence also indicates a one-step mechanism. 2 The secondary KIE produced by changing the hydrogen already attached at the acceptor site from H to D is about 10percent smaller when the transferred atom is D than when it is H.These results, combined with the values of the primary KIE's, strongly suggest some nuclear tunneling in the reaction coordinate.
