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Dienes complexes

Figure I9.2S Schematic reprESeniaiion of the two formal exliemes of bonding in 1,3-diene complexes In (a) the bonding is considered as two almost independent ij -alkene-metal bonds, whereas in (b) diere are a bonds to C(l) and C(4) and an ij -alkene-metal bond from C(2)-C(3)... Figure I9.2S Schematic reprESeniaiion of the two formal exliemes of bonding in 1,3-diene complexes In (a) the bonding is considered as two almost independent ij -alkene-metal bonds, whereas in (b) diere are a bonds to C(l) and C(4) and an ij -alkene-metal bond from C(2)-C(3)...
As shown in Scheme 94, the fj -styrene zirconium complex Cp Zr (f/ -PhCHCH2)[MeC(NPr )2] also served as starting material in the synthesis of alkyl-substituted 1,3-diene complexes of (pentamethylcyclopentadienyl)zirco-nium amidinates. NMR spectroscopy as well as single-crystal X-ray analyses of these complexes revealed that they are best described by the Zr(lV) a, n-metallacyclopent-3-ene limiting resonance form rather than as Zr(ll) f/ -diene complexes. ... [Pg.255]

One of these 1,3-diene complexes, a 1,3-hexadiene derivative, was also obtained in a less straightforward manner by thermally induced loss of "CgHig" from a bis(fj-hexyl) precursor (Scheme 95). ... [Pg.256]

III. NMR SPECTROSCOPIC CHARACTERIZATION AND FLUXIONAL BEHAVIOR A. Conjugated 1,3-Diene Complexes... [Pg.890]

The Rh-catalysed intermolecular [4+2] cycloaddition of a diene and a terminal alkyne affords the l,4-disubstituted-l,3-cyclohexadiene 58 via 57 [18], The 1,2,6-trisubstituted-l,4-cyclohexadiene 60 is obtained by the Fe-catalysed [4+2] cycloaddition of dienes and internal alkynes. The catalyst 59 is prepared by the reaction of a 1,4-diaza-1,3-diene complex of FeCl2 59 with EtMgBr [19]. [Pg.176]

Unconjugated dienes form the 1,3-diene complexes after isomerization to conjugated dienes. Formation of the stable conjugated diene complexe is the driving force of the isomerization. For example, the 1,4-diene in the synthetic intermediate 29 of prostaglandin A can be protected as the diene complex 30 after isomerization to the conjugated diene when it is treated with Fe2(CO)9. This method was applied to the synthesis of prostaglandin C (13). The diene complex 30 is stable for the oxidation of the lactol and introduction of the a-chain [7]. [Pg.357]

Cyclohexadienes are avaiable by the Birch reduction of aromatic compounds, and converted to 1,3-diene complexes by heating with Fe(CO)5. l-Methoxy-1,4-... [Pg.358]

Yasuda, H., Kajihara, Y., Mashima, K., Nagasuna, K., Lee, K. and Nakamura, A. (1982) 1,3-Diene complexes of zirconium and hafnium prepared by the reaction of enediyl-magnesium with MCl2Cp2. A remarkable difference between the zirconium and hafnium analogues as revealed by H NMR and electronic spectra. Organometallics, 1, 388-396. [Pg.65]

The various heterocyclic ligands just described are easily cleaved from the respective molybdenum centers either by reaction with sulfur or through ligand exchange with l,2-bis(diphenylphosphino)ethane (Scheme 17).44a The Diels-Alder cycloaddition is successfully expanded to transient 1-phospha-1,3-diene complexes such as 25 and suitable dienophiles. As illustrated in Scheme 12, the isomeric 1,2-dihydrophosphetes (e.g., 26) are their masked stable precursors. Reaction of 26 with dimethyl acetylenedicarboxy-late or with benzaldehyde furnishes the Diels-Alder adducts of transient 25, compound 71, as a mixture of two isomers, and isomerically pure 72.44b (See Scheme 18.)... [Pg.24]

Dihydrophosphinine Complexes Obtained from a Transient 1-Phospha-1, 3-Diene Complex and Alkynes... [Pg.26]

In this context we report on synthesis and structural features of intermolecular (type C molecule) and intramolecular (type D molecule) donor-stabilized acyclic l-metalla-2-sila-1,3-diene complexes. [Pg.570]

Alkene-functionalized 1,3-diene complexes undergo regio-and stereoselechve 1,3-dipolar cycloaddition reactions with nitrile A-oxides. Related cycloaddihons of nitroalkanes in the presence of triethyl amine and phenylisocyanate afford dihydroisoxazoles. This type of cycloaddition was used in a synthesis toward macrolactin A (Scheme 163). [Pg.3253]

Reduction of TiCLi(THF)2 with 2 equivalents of Mg in the presence of 2 equivalents of a sterically demanding 1-aza-1,3-diene, ArN=CHC(CH3)=CAr (Ar=l,5 (i-pr)2C6H3), gives the homoleptic early transition metal 1-aza-1,3-diene complex, Ti(l-aza-l,3-diene)2. X-ray diffraction analysis of this complex shows Ti-N distances of 1.949(2) and 1.939(2)A and Ti-C distances of 2.317(3) and 2.132(3) A. The subsequent addition of MeLi and elimination of methane... [Pg.4917]

The magnesium-1,3-diene complex (s-m-PhCH=CHCH=CHPh)Mg-(THF)3 (65) was synthesized from 1,4-diphenylbutadiene and activated... [Pg.202]

The preceding pair of resonance descriptions is called the Dewar Chatt Duncanson model of tt bonding. Similar pictures can be drawn for metal-alkyne complexes, regardless of whether the second tt bond is acting as a tt donor, and for metal-1,3-diene complexes. [Pg.274]

Ring-opening between C(l) and C(2) to give 1,3-diene complexes 1S0 151), mostly via I. [Pg.104]

The Isoprene-Fe(CO)3 Radical Complex Various acyclic 1,3-diene complexes were investigated using the B3LYP functional.160 The radical complexes 1 and 2 are formally derived by abstracting a hydrogen atom from the isoprene-Fe (CO)3 complex (Figure 10.18). [Pg.481]


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See also in sourсe #XX -- [ Pg.1072 ]

See also in sourсe #XX -- [ Pg.5 ]

See also in sourсe #XX -- [ Pg.1072 ]

See also in sourсe #XX -- [ Pg.5 ]




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1.3- Dienes coupling with carbene complexes

1.3- Dienes reactions with iron carbene complexes

Alkyl-diene complex

Allyl and buta-1,3-diene complexes

Allyl complexes from 1,3-dienes

Arene complexes from diene

Bicyclo hepta-2,5-diene, ruthenium complex

Bonding models for diene complexes

Buta-1,3-diene complexes

Buta-1,3-diene complexes bonding

Carbenes, alkynyltransition metal complexes cycloaddition reactions with 1,3-dienes

Carbon 13 chemical shifts diene complexes

Chromium electron-deficient diene complexes

Cobalt complexes diene

Complex diene

Complex diene

Complexes Derived from Conjugated Dienes

Complexes Derived from Unconjugated Dienes

Conjugated diene complexes

Conjugated diene complexes 13C NMR spectra

Conjugated diene complexes Diels-Alder reactions

Conjugated diene complexes H NMR spectra

Conjugated diene complexes NMR chemical shifts for

Conjugated diene complexes NMR spectra of, in solution

Conjugated diene complexes Z-isomerization

Conjugated diene complexes acyclic

Conjugated diene complexes cis/trans interconversion

Conjugated diene complexes crystal structure

Conjugated diene complexes cyclic

Conjugated diene complexes cycloaddition

Conjugated diene complexes decomplexation

Conjugated diene complexes deprotonation

Conjugated diene complexes dimerization

Conjugated diene complexes electrocyclic ring closure

Conjugated diene complexes electrophilic additions

Conjugated diene complexes epoxidation

Conjugated diene complexes fluxional behaviour

Conjugated diene complexes halogenation

Conjugated diene complexes hydroacylation of, ruthenium-catalysed

Conjugated diene complexes hydrocyanation

Conjugated diene complexes hydrogenation

Conjugated diene complexes in stereoselective synthesis

Conjugated diene complexes insertion reactions

Conjugated diene complexes isomerization

Conjugated diene complexes nucleophilic additions

Conjugated diene complexes of Cr, Mo and

Conjugated diene complexes of Mn and

Conjugated diene complexes of Nb and

Conjugated diene complexes of Rh and

Conjugated diene complexes of Ru and

Conjugated diene complexes of Ti, Zr and

Conjugated diene complexes of bromine

Conjugated diene complexes of carbenium ions

Conjugated diene complexes of carboxylic acids

Conjugated diene complexes of chlorine

Conjugated diene complexes of fluorine

Conjugated diene complexes of halogen azides

Conjugated diene complexes of hydrochloric acid

Conjugated diene complexes of hydrogen nucleophiles

Conjugated diene complexes of hydrogen sulphide

Conjugated diene complexes of iodine

Conjugated diene complexes of mercury compounds

Conjugated diene complexes of nitrogen nucleophiles

Conjugated diene complexes of oxygen nucleophiles

Conjugated diene complexes of selenenyl compounds

Conjugated diene complexes of selenium nucleophiles

Conjugated diene complexes of sulphenyl compounds

Conjugated diene complexes of sulphur nucleophiles

Conjugated diene complexes oxidation

Conjugated diene complexes phenylsulphonylmercuration

Conjugated diene complexes photopericyclic reactions

Conjugated diene complexes protonation

Conjugated diene complexes reactions with carbon electrophiles

Conjugated diene complexes rearrangement

Conjugated diene complexes reduction

Conjugated diene complexes synthesis

Conjugated diene complexes synthesis/isomerization

Cyclo-octa-1,5-diene complexes, with

Cyclohepta-1,3-diene complexes

Cyclohexa-1,4-diene complexes

Cyclohexa-1,4-diene complexes palladium

Cycloocta-1,5-diene complexes

Cycloocta-1,5-diene complexes iridium

Cycloocta-1,5-diene complexes metal carbonyls

Cycloocta-1,5-diene complexes palladium

Cycloocta-1,5-diene complexes platinum

Cycloocta-1,5-diene complexes rhodium

Cycloocta-1,5-diene complexes ruthenium

Diels-Alder reaction Diene complexes

Diene bimetallic complexes

Diene complexes attack

Diene complexes chelated

Diene complexes chelating

Diene complexes crystal structures

Diene complexes cyclooligomerization

Diene complexes dienes

Diene complexes formation

Diene complexes hydroamination

Diene complexes hydroboration

Diene complexes hydrocyanation

Diene complexes hydrosilylation

Diene complexes intramolecular oxidation

Diene complexes nucleophiles

Diene complexes nucleophilic attack

Diene complexes polymerization

Diene complexes reaction with

Diene complexes, deprotonation

Diene complexes, molybdenum

Diene iron complex

Diene ruthenium complexes

Diene, Dienyl and Arene Complexes

Diene, polymerization dimeric complex

Diene-Iron Carbonyl Complexes

Diene-iron carbonyl complexes acyclic dienes

Diene-iron tricarbonyl complexes

Diene-metal complexes

Diene-metal complexes, protonation

Dienes calcium complexes

Dienes catalysts, cobalt complexes

Dienes catalysts, iridium complexes

Dienes catalysts, nickel complexes

Dienes catalysts, palladium complexes

Dienes catalysts, rhodium complexes

Dienes cationic rhodium complexes

Dienes iron tricarbonyl complexes

Dienes magnesium complexes

Dienes palladium complexes

Dienes reaction with vinylcarbene complexes

Dienes via iron carbonyl complexes

Dienes, acylation complexes

Electrophilic attack 4-diene complexes

Ferrocene, complexes with dienes

Formation of Diene Complexes

Induction diene complex

Iridium complexes cyclo-octa-1,5-diene

Iridium complexes dienes

Iron complexes dienes

Iron complexes, with cyclo-octa-1,5-diene

Iron complexes, with dienes

Irradiation conjugated diene complexes

Magnesium diene complexes

NiCl2 diene complex

Nickel complexes diene dimerization

Nickel-complex-catalyzed reactions dienes

Niobium complexes dienes

Nonconjugated diene complexes

Nonconjugated diene complexes synthesis

Nuclear Magnetic Resonance spectra of diene complexes

Nuclear magnetic resonance spectroscopy of conjugated diene complexes

Nucleophiles chelated diene complexes

Palladium complexes diene

Palladium complexes diene conjugation, allylic intermediates

Pentacarbonyliron diene complexation

Perfluoro-1,3-diene complex

Perfluoro-1,3-diene complex bonding

Platinum complexes cyclo-octa-1,5-diene

Polymeric diene complexes

Properties of Diene Complexes

Resonance structures 1,3-diene complexes

Rhodium cationic diene complex

Rhodium complex catalysts cationic diene complexes

Rhodium complexes cyclo-octa-1,5-diene

Rhodium complexes diene

Rhodium complexes with dienes, arylation

Rhodium/chiral diene complexes

Sulfinyl diene complexes

Tantalum complexes dienes

Transition metal complexes dienes

Transition metal hydride complexes, reactions with dienes

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