101327-85-9Relevant academic research and scientific papers
Non- C2-Symmetric Chiral-at-Ruthenium Catalyst for Highly Efficient Enantioselective Intramolecular C(sp3)-H Amidation
Zhou, Zijun,Chen, Shuming,Hong, Yubiao,Winterling, Erik,Tan, Yuqi,Hemming, Marcel,Harms, Klaus,Houk,Meggers, Eric
, p. 19048 - 19057 (2019/12/04)
A new class of chiral ruthenium catalysts is introduced in which ruthenium is cyclometalated by two 7-methyl-1,7-phenanthrolinium heterocycles, resulting in chelating pyridylidene remote N-heterocyclic carbene ligands (rNHCs). The overall chirality results from a stereogenic metal center featuring either a or Δabsolute configuration. This work features the importance of the relative metal-centered stereochemistry. Only the non-C2-symmetric chiral-at-ruthenium complexes display unprecedented catalytic activity for the intramolecular C(sp3)-H amidation of 1,4,2-dioxazol-5-ones to provide chiral -lactams with up to 99:1 er and catalyst loadings down to 0.005 mol % (up to 11 ?200 TON), while the C2-symmetric diastereomer favors an undesired Curtius-type rearrangement. DFT calculations elucidate the origins of the superior C-H amidation reactivity displayed by the non-C2-symmetric catalysts compared to related C2-symmetric counterparts.
Synthesis of 2-aryl-6-methyl-5-nitroquinoline derivatives as potential prodrug systems for reductive activation
Couch, Gavin D.,Burke, Philip J.,Knox, Richard J.,Moody, Christopher J.
, p. 2816 - 2823 (2008/09/19)
A range of novel 2-aryl-5-nitroquinolines have been synthesised as potential prodrug systems for bioreductive activation. Thus 5-nitroquinoline underwent vicarious nucleophilic substitution at C-6 with bromoform anion to give, after hydrolysis and reduction, the quinoline-6-methanol. Introduction of chlorine at C-2 was followed by palladium-catalysed Suzuki coupling to install the 2-aryl substituent. A fluorescent model 'drug', 7-hydroxy-4-methylcoumarin was coupled to the 6-hydroxymethyl group, and its fragmentation upon reduction of the nitro group was investigated.
Dihalomethylation of Nitroarenes via Vicarious Nucleophilic Substitution of Hydrogen with Trihalomethyl Carbanions
Makosza, M.,Owczarczyk, Z.
, p. 5094 - 5100 (2007/10/02)
Trichloro- and tribromomethyl carbanions generated by deprotonation of haloforms with potassium tert-butoxide in a THF-DMF mixture at ca. -70 deg C react with a variety of carbocyclic and heterocyclic nitroarenes according to the vicarious nucleophilic substitution scheme.The reaction provides an efficient and convenient way for the direct introduction of dihalomethyl substituents ortho and para to the nitro group, which in turn can be hydrolyzed to produce nitroaryl aldehydes.
DIRECT FORMYLATION OF NITROARENES VIA VICARIOUS NUCLEOPHILIC SUBSTITUTION OF HYDROGEN
Makosza, M.,Owczarczyk, Z.
, p. 3021 - 3022 (2007/10/02)
A new method of synthesis of nitroaromatic aldehydes via vicarious nucleophilic substitution of hydrogen with dichloromethyl group and its hydrolysis is described.
DIRECT NITROMETHYLATION OF NITRONAPHTHALENE AND ITS HETEROANALOGUES A NEW METHOD FOR FUNCTIONALIZATION OF NITROARENES
Danikiewicz, W.,Makosza, M.
, p. 3599 - 3600 (2007/10/02)
Some nitroarenes react with nitromethane anion to form nitromethyl derivatives which are easily converted into corresponding nitroaromatic aldehydes.
