Cydoocta-l,5-diene

Wahrend im Cycloocta-l,5-dien beide Doppelbindungen cis-Anordixung besitzen, leitet sich 43 vom trans-trans-Cydoocta-l,5-dien ab. Der Grand konnte nach Srinivasan (280) darin bestehen, daB im angeregten Zustand beide Doppelbindungen trans-konfiguriert sind. 

Azlactones 12 were obtained from hippuric acid (11, R2=phenyl) in higher purity and in better yield than those from N-acetylglycine (11, R2=methyl). The question as to which of the aldehydes, vanillin (10, Rj= acetyl) or veratrumaldehyde (10, R3 = methyl), should be chosen was decided by the availability of the latter at a relatively low price from Italy. By asymmetric hydrogenation applying [Rh(Ph-/ -glup)(cod)]BF4 (see formula 15, cod=ds,ds-cydoocta-l,5-diene, A =tetrafluoroborate) all acid substrates led to higher enantioselectivities than their esters (Tab. 1) [12]. 

Cyclometallapolyselanes, 27 59 Cyclometallation reactions, 26 171 Cydoocta-l,5-diene, iridium complex, 26 122, 27 23... 

RhPC32Hn, Rhodium, (1,4-butanediyl)(-q5-pen-tamethylcyclopentadienyl)(tri-phenylphosphine)-, 22 173 Rh2B2N4P4CMIHl2o, Rhodium(I), tetrakis(l-iso-cyanobutane)bis[methylene(di-phenylphosphine)]di-, bis[tetra-phenylborate(l -)], 21 49 Rh20 C,6Hw, Rhodium(l), bis(-q4-1,5-cycloocta-diene)-di-p.-hydroxo-di-, 23 129 IUitO iiHm, Rhodium(l), bis(i)4-l, 5-cydoocta-diene)-di-p.-methoxy-di-, 23 127 RhiOJ K, Rhodium(I), dicarbonylbis-(p-2-methyl-2-propanethiolato)-bis(trimethyl phosphite)di-, 23 124 Rh2Ol2P4S2HM, Rhodium(I), bis(p.-2-methyl-2-propanethiolato)-tetrakis(trimethyl phos-phite)di-, 23 123... 

Polymeric-ruthenium catalysts have been prepared by the reaction of ( / -cyclo-octa-l,3,5-triene) (// -cycloocta-1,5-diene) ruthenium(0), (// -cydoocta-l,3,5-triene) (COT) (// -cycloocta-1,5-diene) (COD) with polystyrene in hydrogen at room temperature [258]. Elemental analysis, IR and mass-spectrometry data show that in these polymer-metal complexes, two cycloolefin ligands, present in the starting Ru(COT)(COD) complex, are substituted by two phenyl rings of polystyrene ... 

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