56558-30-6Relevant articles and documents
PARP1 INHIBITORS
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Page/Page column 36-37, (2021/01/29)
The present invention relates to azaquinolone compounds of Formula (I), and their use in medicine. Formula (I)
Regiodivergent Enantioselective γ-Additions of Oxazolones to 2,3-Butadienoates Catalyzed by Phosphines: Synthesis of α,α-Disubstituted α-Amino Acids and N,O-Acetal Derivatives
Wang, Tianli,Yu, Zhaoyuan,Hoon, Ding Long,Phee, Claire Yan,Lan, Yu,Lu, Yixin
supporting information, p. 265 - 271 (2016/01/25)
Phosphine-catalyzed regiodivergent enantioselective C-2- and C-4-selective γ-additions of oxazolones to 2,3-butadienoates have been developed. The C-4-selective γ-addition of oxazolones occurred in a highly enantioselective manner when 2-aryl-4-alkyloxazol-5-(4H)-ones were employed as pronucleophiles. With the employment of 2-alkyl-4-aryloxazol-5-(4H)-ones as the donor, C-2-selective γ-addition of oxazolones took place in a highly enantioselective manner. The C-4-selective adducts provided rapid access to optically enriched α,α-disubstituted α-amino acid derivatives, and the C-2-selective products led to facile synthesis of chiral N,O-acetals and γ-lactols. Theoretical studies via DFT calculations suggested that the origin of the observed regioselectivity was due to the distortion energy that resulted from the interaction between the nucleophilic oxazolide and the electrophilic phosphonium intermediate.
Crucial role of β-elimination in determining regio- and chemoselectivity of the rhodium-catalyzed hydroformylation of N -allylpyrroles: A new approach to 5,6-dihydroindolizines
Settambolo, Roberta
scheme or table, p. 2915 - 2921 (2010/10/21)
Rhodium-catalyzed hydroformylation of the chiral (S)-3-alkyl-3-pyrrol-1- ylprop-1-enes at 100 atmospheres total pressure and 25C led to the preferential formation of the branched 3-alkyl-2-methyl-3-pyrrol-1-ylpropanals. At 30 atmospheres and 125°C, the linear 4-alkyl-4-pyrrol-1-ylbutanals were obtained: these aldehydes are not the final products, but evolve into more stable 5,6-dihydroindolizines, with the same optical purity as the starting olefins, via a domino cyclization-dehydration process. According to the generally accepted mechanism for rhodium-catalyzed hydroformylation, the regioselectivity, and then the final chemoselectivity, can be rationalized by taking into account that while at room temperature no -elimination occurs, at high temperature the -elimination involves the branched rhodium-alkyl intermediate only.
