ESR study of paramagnetic intermediates in the low-temperature photochemistry of olefins and pentacarbonyliron

New chemical and stereochemical applications of organoiron complexes

“…Other reported reactions involve the photoinduced, oxidative addition of an aromatic C–H bond of a distal benzyl group to the Fe center [ 522 ], and photoinduced conversion of the (η 5 -C 5 H 5 )Fe(CO) 2 (η 1 -C 5 H 5 ) complex into the ferrocene derivative [ 523 ]; also the photochemistry of some (η 4 -cyclopentadiene)Fe(CO) 3 complexes [ 524 ], and photochemical insertion of alkynes into the PR bridged clusters, e.g., (η 3 -PR)Fe 3 (CO) 10 [ 525 ] and (η 4 -PR) 2 Fe 4 (CO) 11 [ 526 ] have been reported. The low temperature studies also include photochemical reaction of alkenes with Fe(CO) 5 [ 527 ], photochemical reaction of Fe(CO) 2 (NO) 2 with 1,3-butadienes [ 528 ]; also, photochemistry of [Fe 2 (CO) 7 L](L=2,2′-bipyridine, 1,10′-phenanthroline), causing substitution of CO by nucleophiles [ 529 ], and photochemical rearrangement of (η 2 -C 5 Me 5 )Fe(CO) 2 CH 2 SiMe 2 H into (η 5 -C 5 Me 5 )Fe(CO) 2 SiMe 3 [ 530 , 531 ]. The photopolymerization of heptadeca-2,4-diynylferrocenecarboxylate in the monolayer on a water surface has recently been investigated [ 532 ]; the polymerization behavior was found to depend markedly on the molecular packing in the monolayer.…”

Thermal Reactions of Ru(CO)3(C2H4)2 with Acyclic, Non-Conjugated Dienes and Photochemistry of Ru(CO)4(eta(2)-diene) Complexes

“…The difference IR spectrum of Ru(CO)3(1 4 -1,4-Ru(CO) 3 (1 4 -1 ,4-pentadiene) + CO(5) pentadiene) associated with this reaction shows the same bands for product as observed in the thermal reaction of Ru(CO) 3 (C 2 H 4 ) 2 with 1,4-pentadiene,Figure 1, except that the peak at 1992 cm -1 for Ru(CO) 3 (11 4 -1,4-pentadiene) is less obscured by the peak at 1994 cm-1 of Ru(CO) 4 (r1 2 -1,4pentadiene). The complex Ru(CO) 3 (1 4 -1,4-pentadiene) isomerizes to Ru(CO)3(1 4 -1 ,3-pentadiene) as discussed above* with a half-time of -2 min at 298 K. Figure 3b shows IR spectral data for the isomerization reaction.…”