Introduction and extension of ethynyl group using 1,1-dichloro-2,2-difluoroethylene. A convenient route to lithium acetylides and derived acetylenic compounds

Trimethylsilyl‐group containing polyphenylacetylenes for oxygen and ethanol permselective membranes

“…The total yield ( 77.5% ) of route A, in which a triple bond was introduced by 2-methyl-3-butyn-2-01,'~ was better than that (40.6%) of route B, in which a triple bond precursor was introduced by 1,1-dichloro-2,2-difluoroethylene. 16 The lower yield of route B was due to the low yield (58.9% ) of the reaction of p -bromotrimethylsilylbenzene with l,l-dichloro-2,2-difluoroethylene. Therefore, 2methyl-3-butyn-2-01 is a better reagent for introducing a triple bond.…”

“…4 -( 1 -fluor0 -5 2 -dichloroethenyl) trimethylsilylbenzene. 16 To a dry ether solution (45 mL) of 15.6 g (68.2 mmol) 4-(trimethylsilyl) bromobenzene a hexane solution (41.1 mL) of n-butyllithium (68.2 mmol) was added dropwise at 0°C. The solution was stirred for 2 h and was added dropwise to an ether solution of 1,1-dichloro-2,2-difluoroethylene 9.08 g (68.2 mmol) in a dry ice-methanol bath.…”

“…(p-1) 16. To a dry ether solution (45 mL) of n-butyllithium (80.4 mmol) , which was prepared from a hexane solution of n-butyllithium, 10.6 g (40.2 mmol) 4-(l-fluoro-2,2-dichloroethenyl) trimethylsilylbenzene was added dropwise and the solution was stirred for 3 h. The usual work up and distillation gave the product in 77.9% yield (5.46 g).…”

Preparation and Properties of Poly(phenylacetylene) Membranes Containing Perfluoroalkyl Groups

“…7 Tungsten hexachloride obtained commercially was used without further purification. Tetraphenyltin was recrystallized from carbon tetrachloride.…”

Synthesis of Biaryls via Palladium‐Catalyzed [2+2+2] Cocyclization of Arynes and Diynes: Application to the Synthesis of Arylnaphthalene Lignans

“…The organic layer was washed with brine, and dried over Na 2 SO 4 . After removal of the solvent, the residue was purified by column chromatography on silica gel (hexane/AcOEt = 6/1) to give 3i (yield: 28 mg, 36 %) and 3j Following the similar procedure for 3a, the crude product, which was prepared from 3-(naphthalen-1-yl)propiolic acid [25] (1.63 g, 8.3 mmol), the propargylic alcohol 18b [19] (1.09 g, 9.5 mmol), DMAP (310 mg, 2.5 mmol), and DCC (2.79 g, 13.5 mmol) in CH 2 Cl 2 (47 mL) at room temperature for 1.5 h, was purified by column chromatography on silica gel (hexane/AcOEt = 10/1) to give 3k as a yellowish solid; yield: 1. To a solution of methyl 3-[2-(methoxymethoxy)naphthalen-1-yl]propiolate [3c] (571 mg, 2.1 mmol) on MeOH (26 mL) was added 10 % aqueous NaOH solution (21 mL), and the mixture was stirred at room temperature for 1 h. The mixture was acidified by the addition of 1 M HCl aqueous solution, and the mixture was extracted with AcOEt.…”