Structure sensitivity of the Marcus .lambda. for hydride transfer between NAD+ analogs
作者:Maurice M. Kreevoy、Drazen. Ostovic、In Sook Han. Lee、David A. Binder、Gary W. King
DOI:10.1021/ja00210a036
日期:1988.1
Constantes de vitesse et d'equilibre du transfert d'hydrure entre divers pyridinium, quinoleinium, acridinium et phenanthridinium
Constantes de vitesse et d'equilibre du transfert d'hydrure entre divers pyridinium, quinoleinium, acridinium et phenanthridinium
Copper-Catalyzed Regio- and Diastereoselective Additions of Boron-Stabilized Carbanions to Heteroarenium Salts: Synthesis of Azaheterocycles Containing Contiguous Stereocenters
作者:Rajender Nallagonda、Rashad R. Karimov
DOI:10.1021/acscatal.0c04474
日期:2021.1.1
Nucleophilic addition of diborylalkyl reagents to N-alkyl or N-acylpyridinium and related heteroarenium salts has been developed as a key step for the synthesis of nonaromatic nitrogen heterocycles that contain contiguous stereogenic centers. Derivatization of the dihydropyridine products for the synthesis of tetrahydropyridines and piperidines have also been described.
Rhodium-Catalyzed Enantioselective Addition of Boronic Acids to <i>N</i>-Benzylnicotinate Salts
作者:Christian Nadeau、Sara Aly、Kevin Belyk
DOI:10.1021/ja111540g
日期:2011.3.9
The highly enantioselective catalytic asymmetric addition of aryl and alkenylboronic acids to N-benzylnicotinate salt 1 is described. The dihydropyridine 2 reaction products can be converted to synthetically useful piperidines. Application of the methodology to the preparation of enantioenriched quaternary chiral centers is also discussed.
Synthesis of Perfluoroalkyl-Substituted Azines via Nucleophilic Substitution of Hydrogen with Perfluoroisopropyl Carbanions
作者:Rafał Loska、Mieczysław Ma̧kosza
DOI:10.1021/jo062254u
日期:2007.2.1
a new protocol for introduction of perfluoroalkyl substituents into azine rings was elaborated via oxidative nucleophilic substitution of hydrogen. It involves three chemical steps: (i) alkylation of azine with p-MeOC6H4CH2Br, (ii) reaction of the resulting salt with fluorinated carbanions generated in situ from HFP and KF, and (iii) N-deprotection and aromatization of the isolated dihydroazine on
通过在适当的溶剂中用固体KF处理全氟丙烯(HFP)原位生成的全氟异丙基碳负离子会添加到N-烷基吡啶鎓,喹啉鎓和其他叠氮盐中,从而生成具有全氟异丙基的合理稳定的N-烷基二氢嗪。在大多数情况下,加成在杂环的2位进行。这些二氢嗪的稳定性取决于N-烷基和嗪环中存在的其他取代基的性质。在与三氟乙酸酐的反应中,它们中最不稳定的被转化为其稳定的C-三氟乙酰基衍生物。的治疗Ñ苄基或ñ - p-甲氧基苄基-2-全氟异丙基二氢嗪与氧化剂如DDQ或硝酸铈(IV)铵导致苄基C-N键断裂,然后氧化环,得到在芳族环中具有全氟异丙基的吡啶或喹啉。基于这些发现,通过氢的氧化亲核取代,拟订了将全氟烷基取代基引入到嗪环中的新方案。它涉及三个化学步骤:(i)用p -MeOC 6 H 4 CH 2使嗪烷基化Br,(ii)所得盐与从HFP和KF原位生成的氟化碳负离子反应,以及(iii)用CAN处理后,分离出的二氢嗪进行N-脱保护和
Gold(I)‐Catalyzed Nucleophilic Allylation of Azinium Ions with Allylboronates
作者:Luke O'Brien、Stephen P. Argent、Kristaps Ermanis、Hon Wai Lam
DOI:10.1002/anie.202202305
日期:2022.5.23
Gold(I)-catalyzed nucleophilic allylations of pyridinium and quinolinium ions with allylboronates are reported. Transmetalation of the allylboronate with gold produces nucleophilic allylgold(I) species that add to the 4-position of the azinium ion with complete regioselectivity to give functionalized 1,4-dihydropyridines and 1,4-dihydroquinolines. Density functional theory (DFT) calculations provided