Amberly phase

Example This example of an HN-C(O) amide torsion uses the AMBER force field. The Fourier component with a periodicity of one (n = 1) also has a phase shift of 0 degrees. This component shows a maximum at a dihedral angle of 0 degrees and minima at both -180 and 180 degrees. The potential uses another Fourier component with a periodicity of two (n = 2). 

Ethoxylation of alkyl amine ethoxylates is an economical route to obtain the variety of properties required by numerous and sometimes smaH-volume industrial uses of cationic surfactants. Commercial amine ethoxylates shown in Tables 27 and 28 are derived from linear alkyl amines, ahphatic /-alkyl amines, and rosin (dehydroabietyl) amines. Despite the variety of chemical stmctures, the amine ethoxylates tend to have similar properties. In general, they are yellow or amber Hquids or yellowish low melting soHds. Specific gravity at room temperature ranges from 0.9 to 1.15, and they are soluble in acidic media. Higher ethoxylation promotes solubiUty in neutral and alkaline media. The lower ethoxylates form insoluble salts with fatty acids and other anionic surfactants. Salts of higher ethoxylates are soluble, however. Oil solubiUty decreases with increasing ethylene oxide content but many ethoxylates with a fairly even hydrophilic—hydrophobic balance show appreciable oil solubiUty and are used as solutes in the oil phase. 

Adidas, a sporting goods company, has committed to phasing out OSPAR+ substances from its sports shoes, so is ranked amber on the database. However, Adidas has yet to adopt a phase-out policy for its perfume and body care products so the company grading remains red (February 2005). 

A solution of 16.2 g methyltriphenylphosphonium bromide in 200 mL anhydrous THF was placed under a He atmosphere, well stirred, and cooled to 0 °C with an external ice water bath. There was then added 30 mL of 1.6 N butyllithium in hexane which resulted in the generation of a clear yellow solution. The reaction mixture was brought up to room temperature, and 7.0 g 3,4-diethoxy-5-(methylthio)benzaldehyde in 50 mL THF was added dropwise, dispelling the color, and the mixture was held at reflux on the steam bath for 1 h. The reaction was quenched in 800 mL HzO, the top hexane layer separated, and the aqueous phase extracted with 2x75 mL of petroleum ether. The organic fractions were combined and the solvents removed under vacuum to give 12.0 g of the crude 3,4-diethoxy-5-methylthiostyrene as a pale amber-colored oil. 

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