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51.
[reaction: see text] Silver salts in the presence of a chelating ligand efficiently catalyze the stereospecific imination of sulfoxides and sulfides with sulfonylamides and PhI(OAc)(2) to afford sulfoximines and sulfilimines, respectively, in good yields. 相似文献
52.
Copper-mediated cross-coupling reactions of N-unsubstituted sulfoximines and aryl halides 总被引:1,自引:0,他引:1
[reaction: see text] Copper-mediated cross-coupling reactions of sulfoximines with aryl iodides and aryl bromides provide N-arylated sulfoximines in high yields. The method is complementary to the known palladium-catalyzed N-arylation and allows the preparation of N-arylated sulfoximines, which have previously been inaccessible. 相似文献
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55.
Two compounds janoxepin (1) and brevicompanine B (2) were isolated from the fungus Aspergillus janus and the structures elucidated by one- and two-dimensional NMR spectroscopic methods and mass spectrometry. Janoxepin is a novel oxepin derivative with a rare d-leucine incorporated. Brevicompanine B has previously only been isolated from Penicillium brevicompactum. Both compounds were tested in antimicrobial assays and found to be active against the malaria parasite Plasmodium falciparum 3D7 (IC50-values of 28 and 35 mg/ml, respectively). However, no activity was observed in antifungal or antibacterial assays. 相似文献
56.
[reaction: see text] Palladium-catalyzed alpha-arylation of N-benzoyl sulfoximine ethyl ester with various aryl bromides leads to alpha-arylated products that can easily be hydrolyzed, giving the corresponding N-protected benzyl phenyl sulfoximines. In this manner, new sulfoximine derivatives are accessible that have so far been difficult to prepare in enantiopure form. 相似文献
57.
Michael Knorr Isabelle Jourdain Carsten Strohmann 《Journal of organometallic chemistry》2005,690(6):1456-1466
Insertion of hexafluorobutyne into the Pt-H bond of the heterobimetallic complexes [(OC)3Fe{Si(OMe)3}(μ-Ph2PXPPh2)Pt(H)(PPh3)] (1a X = CH2; 1b X = NH) yields the σ-alkenyl complexes [(OC)3Fe{μ-Si(OMe)2(OMe)}(μ-Ph2PXPPh2)Pt{C(CF3)C(H)CF3}] (3a X = CH2; 3b X = NH). This insertion reaction is accompanied by dissociation of the platinum bound PPh3 ligand and saturation of the vacant coordination site by a dative μ−η2-Si-O → Pt interaction. Addition of the Pt-H bond of 1a across the triple bond of 3,3,3-trifluoropropyne affords in a regiospecific manner [(OC)3Fe{μ-Si(OMe)2(OMe)}(μ-dppm)Pt{C(CF3)CH2}] (2) having the trifluoromethyl substituent on the α-carbon. Addition of RNC to 3 affords the isocyanide adducts [(OC)3Fe{Si(OMe)3}(μ-Ph2PXPPh2)Pt(CNR){C(CF3)C(H)CF3}] (4a R = t-Bu, X = CH2; 4b R = 2,6-xylyl, X = CH2; 4c R = 2,6-xylyl, X = NH). In dichloromethane solution 3a is gradually transformed into the C4F6-bridged compound [(OC)3Fe(μ-dppm)(μ-CF3CCCF3)Pt(CO)] 5. The Pt-bound carbonyl ligand of 5 is displaced by xylylisocyanide or trimethylphosphite affording the derivatives [(OC)3Fe(μ-dppm)(μ-CF3CCCF3)Pt(CNxylyl)] 6 and [(OC)3Fe(μ-dppm)(μ-CF3CCCF3)Pt{P(OMe)3}] 7. The molecular structures of 4a, 5 and 6 have been determined by X-ray diffraction studies. 相似文献
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[reaction: see text] Rhodium-catalyzed oxygen transfer was used to generate benzyl 2-silyl-2-oxoacetates in good yields. The hydrogenation of these compounds led to chiral alpha-silyl-substituted alpha-hydroxyacetic acids. Resolution by means of HPLC using a chiral stationary phase afforded an enantiomerically pure representative of this class of compounds, which was successfully applied as a chiral ligand in an asymmetric aldol-type reaction. 相似文献
60.
A polymeric malonato-bridged copper(II) complex, {[Cu(H2O)3][Cu(MAL)2]· 2H2O}, and a mononuclear malonato-copper(II) complex with triethanolamine, [Cu(MAL)(TEA)]·H2O, have been prepared and characterized by elemental analyses, i.r., u.v.–vis, magnetic measurements and single crystal X-ray diffraction. The polymeric complex consists of one-dimensional chains containing the MAL bridged [Cu(H2O)3]2+ and [Cu(MAL)2]2– ions and each MAL ligand simultaneously exhibits chelating bidentate (at one copper atom) and bridging (at the adjacent copper atom) coordination modes. The intrachain Cu1...Cu2 separation is 4.963 Å and the polymeric complex exhibits antiferromagnetic behaviour. In the mononuclear complex, the copper(II) ion is octahedrally coordinated by one bidentate MAL and one tetradentate neutral TEA ligands. The i.r. spectra and thermal decompositions of both complexes are described. 相似文献