Chemistry derived from ruthenium atoms. 1. Dimerization of coordinated 2,3-dimethylbutadiene ligands in M(CO)(diene)2 complexes (M = Ru, Fe). Crystal structure of dicarbonyl[(1,2,3-.eta.:6,7,8-.eta.)-2,3,6,7-tetramethyloctadienediyl]ruthenium

Condensation of 2,3‐Di(methylidene)‐7‐oxabicyclo[2.2.1]heptane Derivatives into Dicarbonyl[η3:η3‐octa‐2,6‐diene‐1,8‐diyl]iron Complexes with Nonacarbonyldiiron. Crystal Structure of (1RS,2RS,3RS,4SR,5RS,6SR,1′RS,2′RS,3′RS,4′SR,5′RS,6′SR)‐Dicarbonyl‐{(2,3,C‐η:2′,3′,C‐η)‐2,2′‐ethylene‐5,5′,6,6′‐tetrakis[(methanesulfonyloxy)‐methyl]‐3,3′‐di(methylidene)‐bis[7‐oxabicyclo[2.2.1]hept‐2‐yl]}iron

“…The C, symmetry of complex 10 is visible in Fig.2. The same local symmetry was also found in complexes 1 [5], 4 [ll], and in (cyc1ooctatetraene)zirconium [Sc]. The projection of part of 10 along an axis going through the bridgehead centers of the bicyclic systems (Fig.…”

“…-The oligomerization of 1,3-dienes with catalysts containing low-valent transition-metal complexes is thought to involve, in many instances, the intermediacy of ([ 1,2,3-q :6,7,8-q)-octa-1,6-diene-l,8-diyl]metal complexes [ 11 [2]. Evidences for such species have been obtained, e.g., by NMR studies of Ni-catalyzed 1,3-diene cyclodimerization [3] [4] and by the X-ray crystal structure of dicarbonyl [( 1,2,3-q :6,7,8-~)-2,3,6,7-tetramethyloctadienediyl]ruthenium (1) obtained by carbonylation of carbo-ny1(2,3-dimethylb~tadiene)~ruthenium [ 5 ] . Although the parent [Fe(q '-alkyl),(CO),] complex has been described already in 1967 by Nesmeyanov and coworkers [6], very few examples of related derivatives have been reported since then [7][8][9].…”

“…Cox et al [5] reported that carbonylation of carbonyl(2,3-dimethylbutadiene),iron in THF gives the corresponding bis(ally1) complex 3 in 19 % yield together with tricarbonyl-(2,3-dimethylbutadiene)iron. Structures of the iron complexes 2 and 3 were deduced from their spectral data.…”

“…On stirring 5 in hexane with an excess of [Fe,(CO)J at 20" for several days, a mixture was obtained from which the known [Fe(CO),(diene)] complex 7 [15] (72-79 YO) and the new [Febis(allyl)(CO),] complex 9 (4-8 %) could by isolated by column chromatography on silica gel. The elemental analysis of 9 confirmed a formula [Fe(CO),(S),], and the 360-MHz 'H-NMR spectrum showed two m at 0.90 and 1.53 ppm (AA ' X X ' pattern), characteristic of a CH,CH, moiety maintaining either the C, or the C, symmetry, and two s at 2.65 and 3.67 ppm, typical of the protons of the methylidene groups coordinated to the Fe(CO), moiety [5] [ 101. The "C-NMR spectrum of 9 displayed typical signals at 38.6, 92.89, and 110.6 ppm for the Fe(q3-alkyl), moiety.…”

Steric and electronic factors influencing the amounts of .mu.-alkylidyne and .mu.-alkenyl products obtained from reaction of diiron methylidyne complexes with alkenes

“…The reaction of 1,2-disubstituted alkenes such as 2butene or cyclohexene with methylidyne complex 1 produces an equilibrating mixture of µ-alkylidyne complexes and µ-alkenyl complexes.6 These equilibrating mixtures react with NaHC03 to produce µ-alkenylidene complexes which arise from deprotonation of the µ-alkylidyne complex. Reaction of 1-d with cis-2-butene gave µ-alkylidyne complex 4 and two isomeric µ-alkenyl complexes 5-E and 5-Z with the deuterium label located exclusively on the methylene group of the ethyl group.6 This labeling result establishes that 1 reacts with c/s-2-butene to produce a (1) Casey, C. P.; Fagan, P. J.; Miles, W. H. J. Am.…”