Synthesis and properties of conjugated bimetallic ruthenium complexes with σ,σ-bridging azobenzene chains

Synthesis and Properties of New Dimeric η2-Diyne Complexes of Cobalt Linked through an Azobenzene Ligand

“…The bond length N–N#1 found in 9 is 1.263(6) Å, similar to those reported in C 6 H 5 CCC 6 H 4 NNC 6 H 4 CCC 6 H 5 (1.264(5) Å), (C 6 H 5 ) 4 C 6 HC 6 H 4 NNC 6 H 4 HC 6 (C 6 H 5 ) 4 (1.263(3) Å), (CH 3 ) 3 SiCCC 6 H 4 NNC 6 H 4 CCSi­(CH 3 ) 3 (1.230(5) Å), {[Co 2 (CO) 6 (μ-HCC)]­C 6 H 4 N} 2 (1.240(5) Å), HCCC 6 H 4 NNC 6 H 4 CCH (1.247(2) Å), and H 3 CC 6 H 4 NNC 6 H 4 CH 3 (1.251(2) Å) …”

“…16,27,29,30 This C−C distance shows a lengthening of ca. 0.15 Å from the value of 1.192(4) Å found in (CH 3 ) 3 Si CCC 6 H 4 NNC 6 H 4 CCSi(CH 3 ) 3 , 26 and this reflects the loss of triple-bond character as a result of coordination of the acetylenic moieties to the Co 2 units. The change in hybridization at C(11)−C (12) is also reflected in the angles C(12)−C(11)−C(1), 139.9(3)°, and C(11)−C(12)− Si (1) The Co−C distances in the "Co 2 C 2 " core of 9 range from 1.955(4) to 1.978(4) Å, and these distances do not show an asymmetry pattern as observed in [{Co 2 (CO) 6 (H C C)} 2 (C 6 H 4 )] 29 and in [Co 2 (CO) 4 (μ-dppm)] 2 (μ-η 2 -HC 2 (C C) 2 C 2 H).…”

Synthesis and reactivity of homo-bimetallic Rh and Ir complexes containing a N,O-donor Schiff base

“…Furthermore, methyl protons of C 5 Me 5 ring are intramolecularly involved in long range C-HÁÁÁp interactions with the phenalato ring. In complex 1, the methyl carbon C13 approaches to C1-C2 bond of the phenalato ring with a contact distance of 2.776 Å (HÁÁÁp 2.776 Å, CÁÁÁp 3.523 Å, C-HÁÁÁp 135.23°), whereas in complex 2 the methyl carbon located at the same position as in complex 1 is involved in a long range interaction with C1-C6 bond of the phenalato ring (HÁÁÁp 3.030 Å, CÁÁÁp 3.503 Å, C-HÁÁÁp 111.86°) [22,23]. Further, crystal structures of 3 and 5 revealed the presence of extensive inter-molecular C-HÁÁÁX (X = F and p) interactions.…”

“…Further, crystal structures of 3 and 5 revealed the presence of extensive inter-molecular C-HÁÁÁX (X = F and p) interactions. It is well established that these types of interactions plays an important role in the construction of huge supramolecular architectures [22,23]. In complex 3, C-HÁÁÁF (C33-H33ÁÁÁF5; 2.599 Å and C4-H4ÁÁÁF3; 2.538 Å), one C-HÁÁÁC-H (C21-H21ÁÁÁC6-H6, 2.397 Å) and FÁÁÁC (C4ÁÁÁF3, 3.140 Å) types of interactions are present.…”

Novel photoswitching dithienylethenes with ferrocene units

“…33 Dithienylethenes with transition metal fragments probably provide new advanced molecular functions and show novel behaviors which are not observed for organic dithienylethenes and their derivatives: MLCT (metal-toligand change transfer) photoisomerization, metal-metal electron transfer reaction, and isomerization-promoted photoluminescence switching. 19,34 It is possible that photoinduced cyclization of the switching unit can be promoted via an efficient energy transfer from the excited metal center to the dithienylethene switch, resulting in a very high photocyclization quantum yield and thermal stability. 35 Although there are a few reports on the synthesis of metal complexes of photochromic diarylethenes, 36 -58 to our knowledge, no dithienylethenes with ferrocene units have been reported.…”