Te-phenyl

Typical procedure Phenyltellurotrimethylsilane (2.10 mL, 10.9 mmol) was added into astirred solution of benzoyl chloride (1.42 g, 10.1 mmol) in 30 mL of dry tetrahydrofuran under an argon atmosphere. The mixture was stirred for 3 h at room temperature and concentrated under a reduced pressure. The residual Te-phenyl tellurobenzoate was purified by recrystallization from pentane to give yellow needles. Yield 2.71 g (87%). 

Aliphatic and aromatic carboxylic acid chlorides cleave the Te —Si bond in phenyl trimethylsilyl tellurium with formation of Te-phenyl carboxylates and trimethylsilyl chloride7. 

When 1-adamantyl phenyl tellurium was treated with sodium in liquid ammonia, the Te-adamantyl bond is preferentially cleaved, although the Te-phenyl bond is also attacked. The ratio of the fragmentation rates is approximately 132. 

Butyl lithium, sec-butyl lithium, tert-butyl lithium, and phenyl lithium cleave Te-phenyl and Te-alkyl bonds in tetrahydrofuran at — 78°. These reactions, in which on organic group bonded to tellurium is exchanged for the organic group associated with the organic lithium compound, are useful for the preparation of organic lithium compounds that are otherwise available only with difficulty or not at all. 

However, when a,a>-bis[4-ethoxyphenyltelluro]alkanes were treated with excess bromine in carbon tetrachloride at 20° for three days, the Te-phenyl bonds were cleaved5. 

In recent years, fluorinated PAs have been explored for gas separation, for PV, and as PEMs in fuel cell application. The high mechanical strength and the film-forming ability of fluorinated PAs have endowed this class of polymers to be used in membrane-based application. In general, a combination of >C(CF3>2 or -CF3 groups and sterically hindered moieties in the same polymer structure has showed improved results in terms of permeability and permselectivity. It is noteworthy to observe that fluorinated PAs containing groups like tert-butyl, adamantyl, te(phenyl)fluorene, and to(phenylphenyl)fluorene showed excellent separation performance for O2/N2 gas pairs and touched or even exceeded the upper bound limit drawn by... 

Fig. 8. Sensitizing dyes of the cyanine class. K. = N — alkyl or chalcogens (O, S, Se, Te) R = chloro, phenyl, or additional benzene ring R = methyl, ethyl, or hydrogen n = 0, 1, 2 and RPRIME, R " = alkyl or sulfoalkyl. Solubihty in methanol for a carbocyanine dye n = 1 X = S R = Cl R = ethyl. Cationic dye (R" = R " = ethyl anion = bromide) 9.5 mmol/T. neutral dye (R" = ethyl R " = sulfopropyl) 3.6 mmol/L anionic dye (R" = R = sulfopropyl ...

A number of less-hazardous reagents that can be substituted for tert-hutyl azidoformate in tert-butoxycarbonylation reactions are available including 2-(te/t-butoxycarbonyloxyimino)-2-phenylacetonitrile (Aldrich Chemical Company), 0-teri-hutyl N-phenyl thiocarbonate (Eastman Organic Chemicals), di-butyl dicarbonate and tert-butyl phenyl carbonate. ... 

Intramolecular heteroatom coordination may also influence the stabilities or structures of catenated tellurium compounds. For example, a rare example of a tritelluride, bis[2-(2-pyridyl)phenyl]tritelluride, is stabilized by a Te N contact of 2.55 The ditelluride (2-MeOCelFtCOTe) has an unusual planar structure. Although the C=0 Te interaction is longer (3.11 A) than the Me 0 contact (2.76 A), ab initio molecular orbital calculations indicate that the planarity results predominantly from the former intramolecular connection. 

The molecular and crystal stmctures of 2-phenylbenzotellurazole were determined by X-ray (89KGS1690). The dihedral angle between the planes of the five-membered heterocycle and 2-phenyl ring is 31.2°. In contrast to benzoisotel-lurazole, no shortened intermolecular Te- N contacts were found in the crystal stmcture of 2-phenylbenzotellurazole. Consequently, no anomalies in solubility and melting point were revealed for this compound as compared with its sulfur and selenium congeners. 

X-ray structures of 2,7-uiphenyloxepin,34 3,7-di-te/7-butyl-5-phenyl-2-(4-tolyl)oxepin,35 and tert-butyl oxepin-2-carboxylate25 and various 3,6-alkanooxepin derivatives36-38 confirmed a nonplanar boat geometry that had already been assumed from spectroscopic data. 

Dimethylamino-l-phenyl-propan4 Zu einer Suspension von 5,9 g (0,15 Mol) Lithiumalanat in 200 ml abs. Diathylather wird unter Riihren und unter Stickstoff eine Losung von 28,2 g (0,15 Mol) 2-Dimethylamino-2-phenyl-butansaure-nitrilin 75 ml abs. Diathylather gegcben. Man riihrt 7 Stdn. bei 20°undarbeitet auf Ausbeu-te 22 g (90% d.Th.) Kp .7 43-44°. 

Ethyl 6-methyl-4-phenyl-2-(phenylthio)-l,4-dihydropyrimidine-5-carboxyla-te was easily synthesized from ethyl 6-methyl-4-phenyl-2-thioxo- 1,2,3,4-tetra-hydropyrimidine-5-carboxylate and phenylboronic acid via microwave-assisted Cu-mediated S-phenylation (Scheme 108) [107]. The reaction involves the use of a stoichiometric amount of Cu(OAc)2 and a two-fold excess of 1,10-phenanthroline as a hgand. 

As described previously, the two dimethyl amino methyl groups on the 2,6-position of the phenyl ring of teluride 161 act as internal ligands (Koten s arms) and stabilize the cation generated at the central Te atom (see Equation 44). Furukawa and co-workers subsequently showed that these Koten s arms also activate the molecule to release alkyl substituents which are attached to the central chalcogen atom <1995JA10153> and <1997BCJ2571>. For example,... 

Figure 2 Structure of te- 2,4-dichloro-6-[(2-dimethylaminoethyl)methylsulfamoyl]-phenyl oxalate dihydrochloride.

In a range of anions PhZ (Z = O, S, Se, Te), for example, the thiophenolate ion (PhS ) effectively traps aryl radicals (Ar ), whereas the anion of phenyl selenide (PhSe ) is 20 times less active, and the phenolate anion (PhO ) is absolutely inactive. The reaction of aryl radicals with phenyl-telluride ions (PhTe ) proceeds in an abnormal fashion—both asymmetrical and symmetrical tellurides are produced (Rossi and Pierini 1980). 

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