نتایج جستجو برای: imines

تعداد نتایج: 2655  

Journal: :Dalton transactions 2015
Shumiao Zhang Xiaoyan Li Hongjian Sun

C,N-coupling reactions of aryl chlorides and aryl amines catalyzed by a nickel catalyst are reported. 17 new amines are synthesized in yields of 57-99%. 2,6-Dichloro substituted imines can be selectively aminated. Both mono- and di-aminated products are obtained. Different substrates and amines are tested to look into the influence of electronic effects and steric hindrance to the reaction. An ...

Quinones such as 1,4-naphthoquinones are abundant in nature and naphthoquinone based natural products are known to possess anticancer activity. This pharmacophore is known to convey anticancer activity to some drugs such as streptonigrin, mitomycin A, etc. We synthesized and characterized different classes of naphthoquinone derivatives including bis naphthoquinone, 2-arylaminonaphthoquinone, be...

2018
Fredrik Schaufelberger Brian J J Timmer Olof Ramström

Catalyst discovery from systems of potential precursors is a challenging endeavor. Herein, a new strategy applying dynamic chemistry to the identification of catalyst precursors from C-H activation of imines is proposed and evaluated. Using hydroacylation of imines as a model reaction, the selection of an organometallic reactive intermediate from a dynamic imine system, involving many potential...

2017
James R Lawson Lewis C Wilkins Rebecca L Melen

The metal-free catalyst tris(2,4,6-trifluorophenyl)borane has demonstrated its extensive applications in the 1,2-hydroboration of numerous unsaturated reagents, namely alkynes, aldehydes and imines, consisting of a wide array of electron-withdrawing and donating functionalities. A range of over 50 borylated products are reported, with many reactions proceeding with low catalyst loading under am...

Journal: :Dalton transactions 2014
Sun-Hwa Lee Georgii I Nikonov

Secondary amides can be reduced by silane HSiMe2Ph into imines and aldehydes by a two-stage process involving prior conversion of amides into iminoyl chlorides followed by catalytic reduction mediated by the ruthenium complex [Cp(i-Pr3P)Ru(NCCH3)2]PF6 (1). Alkyl and aryl amides bearing halogen, ketone, and ester groups were converted with moderate to good yields under mild reaction conditions t...

Quinones such as 1,4-naphthoquinones are abundant in nature and naphthoquinone based natural products are known to possess anticancer activity. This pharmacophore is known to convey anticancer activity to some drugs such as streptonigrin, mitomycin A, etc. We synthesized and characterized different classes of naphthoquinone derivatives including bis naphthoquinone, 2-arylaminonaphthoquinone, be...

Journal: :Angewandte Chemie 2012
Jin Hee Lee Sreya Gupta Wook Jeong Young Ho Rhee Jaiwook Park

Significance: The authors report, that N-unsubstituted imines can be efficiently generated from alkyl azides using a ruthenium catalyst and fluorescent light. Furthermore, an allylation reaction in a one-pot fashion was achieved, leading to homoallylic imines. Comment: The mild reaction conditions allow an asymmetric allylation of in situ generated benzaldimine from benzyl azide. Using the chir...

2005
Yonghua Zhao Nan Jiang Shufeng Chen Cheng Peng Xiaomei Zhang Yaping Zou Shiwei Zhang Jianbo Wang

The methyl diazoacetate and aryl (N-tosyl)imines can be transformed into syn or anti a-hydroxy b-amino esters with high diastereoselectivities in three steps: the base promoted nucleophilic condensation of the methyl diazoacetate and aryl (N-tosyl)imines to give b-(N-tosyl)amino a-diazoesters, followed by oxidation with Oxone to generate a-oxo esters, which were reduced with NaBH4 to yield the ...

Journal: :Angewandte Chemie 2012
Yunfei Luo Andrew J Carnell Hon Wai Lam

Chiral α-branched allylic amines are important building blocks for organic synthesis, and several catalytic asymmetric methods have been developed for their synthesis. For example, enantioselective metal-catalyzed amination of allylic electrophiles 1 , 2 , 3 ] and rearrangement of allylic imidates have proven to be highly effective. An alternative approach to chiral allylic amines that can be a...

Journal: :Chemical communications 2010
Parminder Kaur Suresh Pindi Walter Wever Trideep Rajale Guigen Li

The asymmetric catalytic Strecker reaction of achiral N-phosphonyl imines with Et(2)AlCN has been established. Both free amino alcohols and BINOLs have been proven to be effective catalysts to afford excellent enantioselectivities and yields. The N-phosphonyl group can be readily cleaved under mild conditions and enable purification of crude products by simple washing with hexane. The cleaved N...

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