90905-81-0Relevant articles and documents
PNO ligand containing planar chiral ferrocene and application thereof
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Paragraph 0114-0118, (2021/06/21)
The invention discloses a PNO ligand containing planar chiral ferrocene and application thereof. The PNO ligand containing planar chiral ferrocene is a planar chiral ferrocene-containing and phenol-containing PNO ligand as shown in a general formula (I) or (II) which is described in the specification, or a planar chiral ferrocene-containing and aryl-phosphoric-acid-containingPNO ligand containing as shown in a general formula (III) or (IV) which is described in the specification, or a planar chiral ferrocene-containing and carbon-chiral-phenol-containingPNO ligand as shown in a general formula (V) or (VI) which is described in the specification. The invention provides tridentate PNO ligands and processes for their complexation with transition metal salts or transition metal complexes; the introduction of salicylaldehyde and derivatives thereof, which are simple and easy to obtain, enables the ligands to have a bifunctionalization effect, and -OH in a formed catalyst has stronger acidity and is beneficial to combination with N/O in polar double bonds. Therefore, due to the bifunctionalization effect of the catalyst, the interaction between the catalyst and a substrate can be greatly improved, so a reaction can obtain higher catalytic activity and stereoselectivity.
New dioxo-molybdenum(vi) and -tungsten(vi) complexes with N-capped tripodal N2O2 tetradentate ligands: Synthesis, structures and catalytic activities towards olefin epoxidation
Wong, Yee-Lok,Tong, Lok H.,Dilworth, Jonathan R.,Ng, Dennis K. P.,Lee, Hung Kay
supporting information; experimental part, p. 4602 - 4611 (2010/08/22)
A series of N2O2 tripodal tetradentate ligands derived from di-/tetra-tert-butyl substituted 2-[bis(2-hydroxybenzyl) aminomethyl]X (X = pyridine and benzimidazole) (H2Ln (n = 1-4)) and 8-[bis(3,5-di-tert-butyl-2-hydroxybenzyl)]aminoquinoline (H 2L5) were synthesised through a 4-step reaction scheme involving sequential formylation, reduction, bromination and alkylation. Treatment of H2Ln (n = 1-5) with [WO2Cl 2(dme)] (dme = 1,2-dimethoxyethane) in the presence of triethylamine gave the corresponding cis-dioxotungsten(vi) complexes [WO2(L n)] (n = 1-5). The corresponding molybdenum analogues [MoO 2(Ln)] (n = 1-5) were also prepared from the reaction of [MoO2(acac)2] (acac = acetylacetonate) with H 2Ln (n = 1-3) or [MoO2Cl2(dme)] (dme = 1,2-dimethoxyethane) with H2Ln (n = 4 and 5). All these compounds were fully characterised by a wide range of spectroscopic methods. The molecular structures of [MoO2(Ln)] (n = 2, 4) and [WO2(L2)] were also confirmed by single-crystal X-ray diffraction analysis. The catalytic activities of [MO2(L n)] (M = Mo, W; n = 1-4) towards epoxidation of styrene were also examined.
Mononuclear iron(III) complexes supported by tripodal N3O ligands: Synthesis, structure and reactivity towards DNA cleavage
Wong, Yee-Lok,Mak, Chun-Yin,Kwan, Hoi Shan,Lee, Hung Kay
experimental part, p. 1246 - 1253 (2010/07/05)
A new synthetic route to the known tripodal tetradentate N3O ligand L1 (HL1 = [N-(3,5-di-tert-butyl-2-hydroxybenzyl)-N,N-di-(2-pyridylmethyl)]amine) is reported. The related compounds HLn (n = 2, 3) were prepared by a similar procedure. Treatment of HLn (n = 1-3) with FeCl3·6H2O in hot methanol led to the mononuclear iron(III) complexes [Fe(Ln)Cl2] (1: n = 1, 2: n = 2, 3: n = 3). The solid-state structures of complexes 1 and 2 were determined by X-ray crystallography. [Fe(L1)Cl2] (1) showed effective nuclease activity in the presence of hydrogen peroxide, converting supercoiled plasmid DNA to its linear form.
Synthesis, structures and catalytic properties of iron(III) complexes with asymmetric N-capped tripodal NO3 ligands and a pentadentate N 2O3 ligand
Tong, Lok H.,Wong, Yee-Lok,Pascu, Sofia I.,Dilworth, Jonathan R.
experimental part, p. 4784 - 4791 (2009/02/05)
A new family of N-capped tripodal NO3 proligands N,N-bis(2-hydroxy-3,5-di-tert-butylbenzyl)-N-(2'-hydroxy-5'-R-phenyl)amine [H3(Ln)] [when R= Me, n = 1; R= tBu, n = 2; R = Cl, n = 3] with different substituents in one of the aryl rings and N,N-bis(2-hydroxy-3-tert-butylbenzyl)-N-(2'-hydroxy-5'-methylphenyl)amine [H3(L4)] were synthesised. The preparation of a new pentadentate proligand N-methyl-N,N',N'-tris(2-hydroxy-3,5-di-tert-butylbenzyl) ethane-1,2-diamine [H3(L5)] with an N2O 3 donor set is also reported. Reaction of the proligands [H 3(Ln)] (n = 1-4) with iron(iii) chloride in the presence of base (triethylamine) and 1-methylimidazole (1-Meim) as co-ligand led to the formation of iron complexes of the type [Fe(Ln)(1-Meim)] (n = 1-4) (1-4) respectively, while treatment of the trilithium salt of [H 3(L5)] with iron(iii) chloride afforded [Fe(L 5)] (5). All complexes were structurally characterised by X-ray crystallography. In complexes 1-4, the ligands form five- and six-membered chelate rings with the iron centres which have distorted trigonal bipyramidal geometry with an N2O3 coordination environment. Complex 5 adopts a similar distorted trigonal bipyramidal geometry also with N 2O3 coordination around the iron centre. The catalytic activity of these iron complexes towards epoxidation of styrene was examined.
3,5-Di-(tert-Butyl)-6-fluoro-cycloSal-d4TMP - A Pronucleotide with a Considerably Improved Masking Group
Ducho, Christian,Wendicke, Silke,Goerbig, Ulf,Balzarini, Jan,Meier, Chris
, p. 4786 - 4791 (2007/10/03)
A new, considerably improved cycloSal masking group has been developed. This new group combines four desirable properties and has been attached to the anti-HIV drug 2′,3′-dideoxy-2′,3′-didehydrothymidine (d4T, 1) to give 3,5-(di-tert-butyl)-6-fluoro-cycloSal-d4TMP (2i). This phosphate triester has a reasonable chemical half-life, highly selectively released d4TMP, has poor - if any - inhibitory effect on butyrylcholinesterase (BChE), and achieved the TK-bypass. ( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003).
