Xylene Light Yellow

Fast Light Yellow BG Flavazine Kiton Yellow S Xylene Light Yellow 2GL... 

Polydimethylphenylsiloxane and polymethylphenylsiloxane varnishes are transparent liquids with colour ranging from light yellow to light brown. They can be dissolved in toluene, benzene, xylene and other nonpolar organic solvents but are not soluble in water and alcohols. 

Light yellow oil, aromatic odor, d25 1.268. ng 1.6021. Practically insol in water. Miscible with benzene, toluene, xylene, acetone, isopropanol, methanol. LD, in female, male rats (mg/kg) 7.7, 36 orally 25, 230 derm ally (Gaines). 

Light yellow crystals from xylene or 95% ethanol, mp 189" (uncorr), 193° (corr). Practically insot in water, petr ether, moderately sol in benzene, alcohol, warm carbon tetrachloride very sol in chloroform, ether, acetone, pyridine- uv max (abs ale) 274 nm, Horowitz, Jurd, J. Org. Chem. 26, 2446 (1961). 

PHYSICAL PROPERTIES Colorless, white, or light yellow-green solids faint, pleasant odor benzo(a)pyrene slightly soluble in water, ethanol and methanol soluble in benzene, toluene, xylene and ether MP (179°C, 354 °F) BP (310-312°C, 540-544°F) LSG (1.351) VP (5.6E-09 mm Hgat25 C). 

The mixture of phosphonitrilechloride oligomers is a thick oily liquid ranging in colour from dark yellow to brown. It dissolves well in benzene, toluene, xylene, acetone and some other organic solvents it does not dissolve in water, acetic acid and light petroleum. 

Butyl lithium (0.116 mol) was added dropwise to a solution of 2,7-dibromo-9,9 -dioctylfluorene (0.0918 mol) in 200 ml of THF at —78°C over 45 minutes and then stirred for an additional 30 minutes. The mixture was treated with dimethylformamide (0.1539 mol) at —78°C, warmed to ambient temperature over 4 hours, and concentrated. The yellow residue was dissolved in 130 ml of hexanes/xylenes, 10 3, respectively, and then quenched with 5 ml 20% hydrochloric acid. After separating from the aqueous fraction, the organic layer was neutralized with NaHCOs, filtered, dried over MgS04, and decolorized with activated carbon (10 g). The final solution was filtered and concentrated, yielding a colorless solid with a faint greenish hue. The light greenish color was removed by suspension in methanol, and the product was isolated in 83% yield as a colorless microcrystalline solid with MP = 48-50°C. 

The effects of solvent on the thermal chemiluminescent decomposition of 1 described above are summarized as follows. First, SPD proceeded in an aprotic polar solvent to afford bright light with AniaxSPD = 493-498 nm similar to BID by a CT-induced decomposition mechanism. Second, 1 underwent uncatalyzed TD to give excited 5 which emitted yellow light with A ,axTD = 536 nm due to ESIPT in nonpolarp-xylene. 

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