Syntheses and Spectroscopic Properties

The first reported synthesis (9,76) (78%) of Cp2V2(CO)5 (7) involved protonation of the dianion [CpV(CO)3]2- made by sodium amalgam reduction of CpV(CO)4. No vanadium hydride is isolated in this reaction. A slightly better yield (89%) results from the photolysis of CpV(CO)4 in THF using a falling-film photoreactor (77). The product 7 is produced via dimerization of an intermediate solvent complex CpV(CO)3(THF) followed by a further carbonyl loss (35). The corresponding Cp complex 7 is also available by an exactly analogous photolysis of Cp V(CO)4 or by protonation of [Cp V(CO)3]2- (JO). 

The two semi-bridging carbonyls are manifest by two low frequency stretches, vco(hexane) 1869 and 1828 cm-1 (9). A single Cp signal in the NMR spectrum shows the molecule is fluxional (9). 

Early syntheses of 2 involved high temperature reactions of Mo(CO)6 with acetylpentamethylcyclopentadiene (14,78,79) or Cp H (15,16) itself. These methods are now generally superseded. All species 1-3, l -3, and 

The indenyl complex In2Mo2(CO)4 is also made by thermolysis of the corresponding hexacarbonyl (44,84), while the hydridotrispyrazolylborato complex, Tp2Mo2(CO)4, is best made by the one-electron oxidation of [TpMo(CO)3] with [Cp2Fe]+ (43,85). The heterobimetallic complex Cp2-MoW(CO)4 can be made in respectable yield by thermolysis of a mixture of Cp2Mo2(CO)6 and Cp2W2(CO)6 (81,86). 

Photolysis of Cp Mn(CO)3 in THF leads to the solvent complex Cp Mn-(CO)2(THF). Removal of solvent at -20°C followed by warming to room temperature while maintaining reduced pressure results in dimerization of solvent complex, decarbonylation, and solvent loss to form the air-sensitive 8 (17,51,88). While not isolated, the related Cp complex 8 has been observed in the gas phase. It is seen, in the electron-impact mass spectrum of the THF complex CpMn(CO)2(THF), which shows a molecular ion and cracking pattern assignable to 8 rather than the THF complex itself (51). The rhenium complex 9 is formed on photolysis of Cp Re-(CO)3 in THF (18) and in the carbonylation (15-20 atm, THF or toluene) of Cp 2Re2(0)2(ju.-0)2 (89,90). 

---

Jiao GS, Loudet A, Lee HB, Kalinin S, Johansson LBA, Burgess K (2003) Syntheses and spectroscopic properties of energy transfer systems based on squaraines. Tetrahedron 59 3109-3116... 

Loudet A, Burgess K (2007) BODIPY dyes and their derivatives syntheses and spectroscopic properties. Chem Rev 107 4891 1932... 

Gebhard and coworkers42 reported a synthesis and spectroscopy of chemically modified spheroidenes. The structure and numbering of the system is shown in 66. The syntheses and spectroscopic properties of the all-E isomers of 1112 dihydrospheroidene (67),... 

In this chapter we introduce compounds which have been successfully applied in the construction of supramolecular assemblies. Only the amphiphiles which have been prepared in sufficient quantities have been admitted milligram quantities being considered unacceptable as starting materials for the preparation, analysis and application of assemblies. Experience proves that complicated dyes, pore builders, receptors etc. never reappear in the literature after their syntheses and spectroscopic properties have been reported. On the other hand, such easily attainable synkinons and surfactants around the ten gram scale need not, of course, be too simple. On the contrary, they may contain all the components of the chiral pool, i.e. amino acids, carbohydrates, steroids etc., as well as all commercial dyes of interest such as protoporphyrin, phthalo-cyanines, carotenes, viologen and quinones. 

Syntheses and spectroscopic properties of BODIPY dyes and their derivatives (BODIPY is4,4-difluoro-4-bora-3a,4a-diaza-s-indacene) 07CRV4891. 

Boland, W., N. Schroer, C. Sieler, Stereospecific Syntheses and Spectroscopic Properties of Isomeric 2,4,6,8-Undecatetraenes. New Hydrocarbons from the Marine Brown Alga Giffordia mitcheUae, Helv. Chim. Acta 70 1025—1040 (1987). 

N. Le Narvor, L. Toupet, C. Lapinte - Elemental Carbon Bridging Two Iron Centers. Syntheses and Spectroscopic Properties of Cp (dppe)FeC4-FeCp (dppe)" nPF6 X-Ray Crystal Structure of the Mixed Valence Complex (n = 1),... 

B. Hydroxide Derivatives of Zinc and Cadmium 1. Syntheses, Structures, and Spectroscopic Properties... 

From the standpoint of modeling Type I copper proteins,4,5,59,60 a variety of imidazole-based ligands containing thioether sulfurs and imidazole groups have been synthesized.61,62 The structures and spectroscopic properties of their copper(II) complexes (51)-(53) and (55)-(60) were investigated.65,79-82 To characterize apical copper(II)-thioether bonding, the complex (51) was... 

Tetrakis(2,2,3,3,4,4, 5, 5 -octafluoropentoxy) phthalocyanine zinc was synthesized and characterized demonstrating the effects of the strongly electron-withdrawing groups on the electronic and spectroscopic properties of the complex.832 Zinc phthalocyanate,... 

Various combinations of tricoordinate heavy ketones have been synthesized as stable compounds by taking advantage of extremely bulky aryl substituents.52 54,161 167 Table 3 shows their selected structural parameters and spectroscopic properties. 

The PFg" salts of [Ru(bpy)2(110)] and [Ru(110)3] and analogous complexes containing 4,4 -bis(substituted) ferrocenyl ligands (110 ), have been synthesized and characterized the tris(chelate) complexes are either poorly soluble or insoluble. Electropolymerization of [Ru(110 )3][PF6]2 produces an electrochromic film. The complex [Ru(bpy)2(lll)] undergoes electropolymerization on Pt and glassy carbon electrodes, although the related complex [Ru(bpy)2(112)] does not. Electrochemical and spectroscopic properties of the films indicate that they form by both head-to-tail and tail-to-tail monomer coupling. ... 

In the following sections the physicochemical and spectroscopic properties, reactions, syntheses, and, more briefly, utilization of these ring systems are discussed. Within the individual sections the pyrido[2,l-b][l,3]oxazines and their benzologs and pyrido[2,l-b][l,3]thiazines and their benzologs are dealt with. 

This article covers the primary chemical literature published between the second half of 1981 and 1993 and contained in Chemical Abstract Chemical Substance Indexes, Volumes 95-119 inclusive. Pertinent 1994 literature is also included. In the following sections the physicochemical and spectroscopic properties, syntheses, reactions, and more briefly, the... 

Coe, B. J., Jones, L. A., Harris, J. A., et al., Syntheses and spectroscopic and quadratic nonlinear optical properties of extended dipolar complexes with ruthenium(II) ammine electron donor and N-methylpyridinium acceptor groups. J. Am. 

The chemistry of Mo(II) and W(II) alkyne monomers constitutes the remainder of this article. Among the array of syntheses, structures, spectroscopic properties, and reactions, two sections deserve advertising. 

---