SYNTHESIS AND STEREOCHEMISTRY OF PENTACARBONYL(PHOSPHOLE)METAL(0) AND TETRACARBONYLBIS(PHOSPHOLE)METAL(0) COMPLEXES OF 6B ELEMENTS

1992-01-01
OZER, Z
Özkar, Saim
Pentacarbonylphospholemetal(0) and cis-tetracarbonylbis(phosphole)metal(0) complexes were synthesized from the thermal reaction of M(CO)5(THF) and M(CO)4(COD) (M: Cr, Mo, W) with corresponding phosphole (1-phenyl-3,4-dimethylphosphole, 1-phenyl-3-methylphosphole, and 1-phenylphosphole). These complexes were isolated as orange crystals by column chromatography on silicagel at 253 K and crystallization from n-hexane at 223 K and characterized by means of IR and NMR (H-1, C-13, and P-31). Spectroscopic data shows that the phosphole is coordinated to the transition metal through its phosphorus atom rather than through the conjugated diene unit in the both types of complexes. The tetracarbonylbis(phosphole)metal(0) complexes were found to have cis-arrangement of two phosphole ligands. Comparing C-13-NMR chemical shifts of the complexes with the free ligands, one can deduce that the involvement of the phosphorus atom in the ring pi-electron delocalization is drastically reduced upon coordination. This is attributed to the stronger sigma-donation but weaker pi-accepting ability of the phosphorus atom in the phosphole ligands compared to the carbonyl groups.
PHOSPHORUS SULFUR AND SILICON AND THE RELATED ELEMENTS

Suggestions

Synthesis, characterization, and electrochemistry of tetracarbonyl(6-ferrocenyl-2,2 '-bipyridine)tungsten(0)
Edinc, Pelin; Oenal, Ahmet M.; Özkar, Saim (Elsevier BV, 2007-04-15)
6-Ferrocenyl-2,2'-bipyridine (fcbpy) was prepared by the reaction of lithiated ferrocene with bipyridine and employed as a bidentate ligand for the formation of tetracarbonyl(6-ferrocenyl-2,2'-bipyridine)tungsten(0). The labile complex pentacarbonyl[eta(2)-bis(trimethylsilyl)ethyne]tungsten(0) reacts with fcbpy in CH2Cl2 to yield the disubstitution product, W(CO)(4)(fcbpy), which was isolated as analytically pure substance and characterized by elemental analysis, IR, UV-Vis, MS, H-1 and C-13 NMR spectroscop...
Insertion of Fischer Carbene Complexes into the Carbon-Carbon Bond of 1,2-Diphenylcyclopropenone: Formation of Cyclobutenones and o- and p-Methoxyphenol Derivatives
Zora, Metin (American Chemical Society (ACS), 1994-08-01)
Thereactionbetween1,2-diphenylcyclopro-penoneandFischercarbenecomplexeshasbeeninves-tigated.Thereactionproducedamixtureofdipheny-lacetyleneandcyclobutenones.Whena,ß-unsaturatedcarbenecomplexeswereemployed,benzannulationprod-uctsanddiphenylacetylenewereproduced.Amecha-nisminvolvingmetallacyclobutenoneformation,followedbyeithercarbeneinsertionandreductiveeliminationorfragmentationhasbeenproposed.Recently,wereportedthatcarbon—carbonbondin-sertionisthemajorreactionpathwaywhenFischercarbenecomplexesreactwith1,2-...
Dipole moments of some styrene copolymers
Küçükyavuz, Zühal; Baysal, Bahattin (American Chemical Society (ACS), 1988-7)
Dipolemomentsofpoly(styrene-co-p-chlorostyrene),poly(styrene-co-p-methoxystyrene),poly(styrene-co-4-vinylpyridine),andpoly(styrene-co-N-vinylcarbazole)copolymersweredeterminedintoluenesolutionsatdifferenttemperatures.Thesamplesweresynthesizedbyusingfree-radicalinitiators.Theeffectsofthenatureofthepolargroup,composition,andtemperatureonthedipolemomentratiowereinvestigated.Themean-squaredipolemomentperstructuralunitshowsapositivedeviationfromlinearity,inagreementwithcalculationsbyMarkbasedonrotationalisomeric...
Selective recognition of anionic cell membranes using targeted liposomes coated with zinc(II)-bis(dipicolylamine) affinity units
Türkyılmaz, Serhan; Palumbo, Rachael; Smith, Bradley D. (Royal Society of Chemistry (RSC), 2014-08-14)
Zinc(II)-bis(dipicolylamine) (Zn(2)BDPA) coated liposomes are shown to have high recognition selectivity towards vesicle and cell membranes with anionic surfaces. Robust synthetic methods were developed to produce Zn(2)BDPA-PEG-lipid conjugates with varying PEG linker chain length. One conjugate (Zn(2)BDPA-PEG(2000)-DSPE) was used in liposome formulations doped with the Lipophilic near-infrared fluorophore DiR. Fluorescence cell microscopy studies demonstrated that the multivalent Liposomes selectively and ...
Resolution of (+/-)-anti-2,3-dioxabicyclo[2.2.2]oct-7-en-5-ol via Candida cylindracea lipase: synthesis of (-)- and (+)-proto-quercitol
GÜLTEKİN, M SERDAR; Celik, M; TURKUT, ENGİN; Tanyeli, Cihangir; BALCİ, METİN (Elsevier BV, 2004-02-09)
Photooxygenation of cyclohexa-1,4-diene afforded anti-2,3-dioxabicyclo[2.2.2]oct-7-en-5-yl hydroperoxide. The hydroperoxy endoperoxide was reduced with dimethylsulfide-titanium tetraisopropoxide to produce ()-anti-2,3-dioxabicyclo[2.2.2]oct-7-en-5-ol. The highly efficient enantioselective resolution of the racemic (+/-)-anti-2,3-dioxabicyclo[2.2.2]oct-7-en-5-ol was accomplished with Candida cylindracea lipase (CCL) to produce the enantiomerically enriched alcohol and the corresponding acetate: The cleavage ...
Citation Formats
Z. OZER and S. Özkar, “SYNTHESIS AND STEREOCHEMISTRY OF PENTACARBONYL(PHOSPHOLE)METAL(0) AND TETRACARBONYLBIS(PHOSPHOLE)METAL(0) COMPLEXES OF 6B ELEMENTS,” PHOSPHORUS SULFUR AND SILICON AND THE RELATED ELEMENTS, pp. 339–349, 1992, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/36345.