178534-74-2

Upstream product

• 199620-14-9 chromium⁽⁰⁾ hexacarbonyl 
• 2719-27-9 cyclohexanylcarbonyl chloride 

Downstream Products

• 178534-82-2 pentacarbonyl(methyl(1-propynyl)thioether-S)chromium 
• 178534-76-4 pentacarbonyl(2-methyl-1-methylthio-4,5,6,7-tetrahydro-3aH-indene-S)chromium 
• 199620-14-9 chromium⁽⁰⁾ hexacarbonyl 

Relevant academic research and scientific papers

Ring expansion of spirocydie ligands in pentacarbonylchromium complexes to tetrahydroindene derivatives

Pentacarbony 1 (pentamethylenevinylidene) chromium, [(CO)5Cr=C=C(CH2)5] (1), reacts with 1-methylthio-l-propyne (2a) and N-(1-propynyl)phenothiazine (2b) by regiospecific addition of the C=C bond of the alkyne to the C=C bond of the vinylidene ligand of 1. Initially, complexes with a spirocyclic cyclobutenylidene ligand are formed, [(CO)5Cr=CC(Me)=C(SMe)t(CH2)5] (3) and [(CO)5-Cr=C-C(Me)=C{N(C6H4) 2S}C(CH2)5] (10). Subsequent thermally initiated ring expansion affords the 2-methyl4,5,6,7-tetrahydroindenyl(methyl)thioether complex [(CO)5Cr-S(Me)(Me-C9H10)] (4) and the N-(2-methyl-4,5,6,7-tetrahydroindenyl)phenothiazine complex f(CO)5Cr-S(C6H4)2 N-(Me-C9H10)] (11), respectively. In both complexes, 4 and 11, the ligand is coordinated to the metal via the sulfur atom. The constitutions were established by (H,H)-, (H,C)- and NOE-correlated NMR spectroscopy. In the reaction of 1 with 2a, in addition to 3 and 4, the metfayl(propynyl)thioetner complex f{CO)5Cr-S(Me)C=CMe] (5) was formed. An isolable 3-methylthio-substituted cyclobutenylidene complex, [(CO)5Cr=C-C(Me)=C(SMe}CPh2] (9) was obtained from [(CO)5Cr=C=CPh2] (8) and 2a. The 4,5,6,7-tetrahydroindenylthioether ligand of 11 was cleaved from the metal by exposure of 11 adsorbed on silica gel to air or by treatment of 11 with [NEt4]Br in dichloromethane. VCH Verlagsgesellschaft mbH, D-69451 1996.

Synthesis and crystal structure of novel 1,3-heterobinuclear complexes with an unusual cyclic C4R3 bridging ligand

Pentacarbonyl(dimethylvinylidene)chromium, [(CO)5Cr=C=CMe2] (1), reacts with the alkynyl complexes [Cp(CO)2FeC≡CR] (4a-e; R = nBu (a), Me (b), Ph (c), C6H4NO2-P (d), COOMe (e)), [Cp(CO){P(OMe)3}FeC≡CnBu] (6), [Cp(CO){PPh3}FeC≡CnBu] (8), and [Cp-(PEt3)NiC=CnBu] (19) by cycloaddition of the C≡C bond of the alkynyl complexes to the C=C bond of 1 to give [(CO)5Cr-C-CR-C(CMe2)-Fe(CO)2Cp] (5a-e), [(CO)5Cr-C-C-(nBu)-C(CMe2)-Fe(CO){P(OMe) 3}Cp] (7), [(CO)5Cr-C-C(nBu)-C(CMe2)-Fe(CO)-{PPh 3}Cp] (9), and [(CO)5Cr-C-C(nBu)-C(CMe2)-Ni(PEt 3)Cp] (20), respectively. The analogous reaction of [(CO)5Cr=C=C(CH2)5] (2) with 4a and 6 affords complexes with a spirocyclic bridging ligand: [(CO)5Cr-C-C(nBu)-C{C(CH2) 5}-Fe(CO)2Cp] (10) and [(CO)5Cr-C-C(nBu)-C{C(CH2) 5}-Fe(CO){P(OMe)3}Cp] (11). Cycloaddition of 4a to [(CO)5Cr=C=CPh2] (3) yields [(CO)5Cr-C-C(nBu)-C(CPh2)-Fe(CO)2Cp] (12). The spectroscopic data of these novel 1,3-heterobinuclear complexes indicate the delocalized π-system Cr-C-C-C-M (M = Fe, Ni). X-ray structural analyses of the compounds 5e, 10, and 11 reveal a butterfly conformation. The puckering angle of the four-membered ring is 160.0° (5e), 143.9° (10), and 144.9° (11). Both C(sp2)-C(sp2) bonds are almost equal in length. All complexes exhibit negative solvatochromic behavior. The extent of the solvatochromic effect is strongly influenced by the substituents at C-2 and C-4 of the ring.