Halogens hexyl

VerhaltnismaBig leicht verlauft die — oft unerwiinschte — Bildung von Alkyl-quecksil-ber-Verbindungen bei der Elektrolyse von Halogen-Verbindungen an einer Quecksil-ber-Kathode. So erhalt man z. B. aus Perfluor-l-jod-hexan in DMF/Lithiumperchlorat an einer Quecksilber-Kathode bei —0,35 V bzw. bei —0,75 bis —0,85 V Perfluor-hexyl-quecksilberjodid und Bis-[perfluor-hexyl]-quecksilber ( 100% d.Th.)9. 

THF or ether) or of the halogen has little effect. However, asymmetric induction is low when R is methyl or allyl, and highest when R is n-hexyl. 

Reaction LXVIH. Simultaneous Reduction and Halogenation of Poly-hydric Alcohols. (A., 138, 364.)—When polyhydric alcohols are heated with hydriodic acid, reduction of all the hydroxyl groups save one occurs this latter is replaced by iodine to form a secondary iodide. In this way, e.g., dulcitol, or any of the hexose alcohols, yields normal secondary hexyl iodide this is of importance in determining the chain structure of the sugars. This reaction probably occurs—... 

Construction of the thiomorpholine moiety starts by protection of the carboxylic acid in penicillamine (102) by reaction with hexyl dimethylsUane (Dmhs). Condensation of 103 with 1,2-dichloroethane leads to formation of the heterocychc ring by sequential displacement of halogen by nitrogen and sulfur to yield 104. Reaction of intermediate 104 with the benzophe-none (101), leads to formation of the sulfonamide (105). Mild acid then serves to reveal the free carboxyhc acid (106). This function is then converted to the acid chloride with oxalyl chloride. Treatment of this reactive intermediate with hydroxylamine leads to acylation on nitrogen to afford the proteinase inhibitor 107. ... 

During the search for homogeneous systems in which the tetravalent perhalotellurium compounds would undergo addition to an alkene, trimethylchlorosilane, acetyl chloride, or acetyl bromide were found to be a convenient source of halogens for the conversion of tellurium dioxide to a tellurium tetrahalide88. Addition of twice the stoichiometrically required amount of cyclohexene to a solution of tellurium tetrahalide, thus generated in either acetic acid, dichloromethane or ethanol-free chloroform leads to the formation of (fra i-2-halocyclo-hexyl)tellurium trihalides in ca. 70% yield. When dry methanol is used as solvent, trans-2-... 

Bonds to Halogens.—Reactions between AsF3 and the negative ions formed mass spectrometrically lead to AsF ( as the predominant secondary ion, whereas in AsF5, both AsFj and AsF<( are formed.629 A series of new fluoroarsinic acid esters F As(OR)3 n, with n = l or 2 and R = methyl to hexyl, result from either alcoholysis of the trifluoride or redistribution reactions between mixtures of the trifluoride and trialkoxide.630 The product identities were confirmed by 19F and H n.m.r. spectroscopy. 

Magnesium dialkyls, R Mg, and the alkyl magnesium halides, RMgX (where R is an alkyl groups such as n-butyl or //-hexyl and X is a halogen)... 

Between w-hexyl and w-heptyl side chains there lies a difference of homology, which represents one of several shoals of obviousness. Another is the choice of alkali metals or halogens lying immediately above or below one another in the periodic table. No new patent application necessarily escapes obviousness by claiming, say, a chlorophenyl substituent instead of a fluo-rophenyl or bromophenyl group that an older patent protects. Other obstacles are salts and isomers of various kinds. 

The formation of aryl ethers of (hydroxyalkyl)-phosphonic or -phosphinic derivatives from the corresponding haloalkyl phosphorus(V) acid derivative and a metal phenate may present unfortunate difficulties depending on the particular halogen, but these have been overcome by the use of sulphonate substrates, in particular the 0-4-chlorobenzenesulphonyl esters of the phosphonic or phosphinic derivative, in reactions with sodium phenates. A study of the alcoholysis reactions of the O-p-tosylates of the cis and trans isomers of diethyl (2-hydroxycyclo-hexyl)phosphonate, has shown that with a 60° dihedral angle between the two functions, the rate of reaction is sensitive to solvent nucleophilicity, and the evidence supports a bimolecular displacement. When the dihedral angle is 180°, the lack of dependence of rate on solvent and other features, support the involvement of carbocationic intermediates, with their stabilization by the phosphono group . ... 

---