Furnishing, color-changing

To a solution of 59a (3.0 g, 7.1 mmol) in toluene (20 mL) was added, with stirring, hexa-chloroethane (1.7 g, 7.1 mmol). The reaction mixture was stirred at room temperature for five days, during which time its color changed from red to yellow. The solvent was then evaporated under high vacuum, the residue was taken up in n-pentane, the insoluble zirconocene dichloride was removed by filtration through Celite, and the residue washed with n-pentane. The filtrate and washings were concentrated and then cooled to -78°C to furnish 53 a (2.2 g, 78%) as pale yellow crystals, m.p. 241 °C. 

In order to confirm this reaction route and at the same time to keep the reaction process as simple as possible, the symmetrically substituted tetraaryldisilene 9 [8] was prepared by the method of West et al. [9] and allowed to react with an excess of lithium. The observed color changes, first to dark green and then to brown-red, suggest the initial transfer of an electron to an aromatic residue [10], followed by extrusion of LiR and formation of the postulated disilenyllithium compound. In a second step of the reaction sequence, 10 was allowed to react with bromomesitylene in anticipation that the poor solubility of the aryllithium compound would favor the halogenation over the competing transarylation. It appears that the bromodisilene 11 is indeed formed and then reacts further with 10 by intermolecular cleavage of lithium bromide to furnish the isolated hexaaryltetrasilabuta-1,3-diene 12 (Scheme 5) [II]. 

Mesoxalic acid esters tend to undergo cycloaddition reactions at their central carbonyl function. Treatment of complex 37 with an excess of diethyl mesoxalate furnished the oxadiphosphatricyclo[3.1.0.0 ]hexane 40 as a colorless oil in 17% yield after chromatography (Scheme 15). When a threefold excess of tetracyanoethene was added to a solution of 37 in dichloromethane at —85 °C the color of the reaction mixture changed spontaneously from red to black, and 1,6-diphos-phatricyclo[3.1.0.0 ]hexane 41 was isolated in 15% yield (Scheme 15) <1999S639>. 

To a solution of ethyl A-phenylacetimidatc (4g, 0.025 mol) in benzonitrile (30 mL) was added freshly sublimed AICI3 (3.5 g, 0.025 mmol). The mixture was heated for 20 min at 170-180°C. During this time it changed color to yellow-brown. The excess benzonitrile was removed by steam distillation and the residue was digested with Et O. The ether solution was dried and evaporated to give an oil which crystallized to furnish 2-methyl-4-phenylquinazoline yield 3.96g (72%) mp47 C. 

Fashion is a concept as well as a market sector, as a distillation of colors and moods rather than necessity, and the promotion of a desire for change. Homewares as furnishing items, functional items such as towels, and decorative items are increasingly... 

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