Pentane, l,5-bis

S- and Se-donor ligands. The e.s.r. and electronic spectra of [Co(sacsac)2] and [Co(sacsac)2L] (sacsac = dithioacetylacetonate, L = py or piperidine) have been studied, and a polarographic study of [Co(sacsac)J (n = 2 or 3) in acetone has shown the complexes to have a well-defined capacity to accept one or two electrons in a reversible stepwise manner. The magnitude of the potentials and their reversible nature suggest that isolation of cobalt-sacsac complexes of low formal oxidation states should be possible." Co complexes of l,5-bis-(2-methylmercaptoethylthio)pentane are both hydrated and polymeric, and thermal decomposition in air or nitrogen leads to oxida tion to Co . Ethylenethiourea (etu) and tetramethylthiourea (tmtu) form the complexes [Co(etu) ](N03)2 and [Co(tmtu) ](C10 )2, which are tetrahedral, and [Co(etu)2(N03)2] and [Co(tmtu)2(N03)2] which have distorted octahedral co-ordination. 3-Diphenylphosphinothioyl-l-phenylthiourea, -1,1-diethyl-thiourea, and -1,1-dimethylthiourea form complexes with Co in which the ligands are bidentate. ... 

To complete the section on the synthesis of 4,4 -bipyridines, we summarize the methods reported for the preparation of some substituted 4,4 -bi-pyridines and 4,4 -bipyridinones. These methods are closely analogous to syntheses already discussed for some of the isomeric bipyridines. Thus the Hantzsch reaction using pyridine-4-aldehyde, ethyl acetoacetate, and ammonia gives 3,5-di(ethoxycarbonyl)-1,4-dihydro-2,6-dimethyl-4,4 -bipyridine, which after oxidation, followed by hydrolysis and decarboxylation, afforded 2,6-dimethyl-4,4 -bipyridine. Several related condensations have been reported. Similarly, pyridine-4-aldehyde and excess acetophenone gave l,5-diphenyl-3-(4-pyridyl)pentane-l,5-dione, which with ammonium acetate afforded 2,6-diphenyl-4,4 -bipyridine. Alternatively, 1-phenyl-3-(4-pyridyl)prop-2-enone, A-phenacylpyridinium bromide, and ammonium acetate gave the same diphenyl-4,4 -bipyridine, and extensions of this synthesis have been discribed. Condensation of pyridine-4-aldehyde with malononitrile in the presence of an alcohol and alkaline catalyst produced compounds such as whereas condensations of... 

Pentane l,3-Bis-[penlafluoro-phenyl]- , 5-dioxo-hexafluoro-ElOb,. 427 (F —OC — A —CO —F + h5C6 —SiR3)... 

Pentane 1.5-Bis-[4-methyl-ben7enc-sul onyloxy]-2,2,3,3,4,4-l>exafluo-ro- ElOb, 633 (Educt)... 

In a similar fashion, cycloaddition reaction of 2-vinylpyrrolidines with carbodiimides in the presence of Pd(OAc)2 and l,5-bis(diphenylphosphino)pentane affords the seven-membered ring cyclic arylguanidines in acceptable yields and conversions (Equation 16) <2004T73>. 

Our studies revealed that, upon treatment of Cul with l,5-bis(phenylthio) pentane in acetonitrile solution, the architecture of the resulting polymeric material depends in a crucial manner on the metal to ligand ratio employed. Performing the reaction in a 2 1 molar ratio gave air-stable crystals of general... 

The majority of syntheses of 4/7-pyrans derive from the ring closure of 1,5-dicarbonyl compounds or their equivalents, which is discussed in detail in the previous volumes <1984CHEC, 1996CHEC-II> and is also the subject of a recent review <2000CHE1007>. In this manner, 2,6-bis(silyl)-47/-pyrans 79 are synthesized by the cyclodehydration of their corresponding l,5-bis(silyl)pentane-l,5-diones in good yield (Equation 43) <2000S843>. 

Figure 14. APCI mass spectrum of l,5-bis(2-hydroxyethylsulfinyl)pentane...

Diphosphoniatricyclo[4.4.4.0]tetradecane bis-triflate 302 was obtained by the reaction of l,5-bis(trifluorometha-nesulfonyloxy)pentane with l,6-diphosphabicyclo[4.4.0]decane 179 in 35% yield in a polar solvent, for example, MeCN. Tricyclic [4.4.4.0]tetradecane 302 was reacted with different nucleophiles to give corresponding bridgeheaded biphosphines 304-308. 

Figure 52 Mechanism of the proton transfer reactions during the cation-radical polymerization of methyl-substituted l,5-bis(phenoxy)pentane monomers. (From Ref. 214.)...

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