Duran glass tubes

A solution of 0.85 g (5.18 mmol) of 1.1.15b, 1.4 g (13.85 mmol) of triethylamine (2.5 eq.) and 100 )iL of decane in 20 nfL of dry acetonitrile was degassed by argon bubbling and distributed among 10 mL Duran glass tubes. After purging the tubes with argon for 1 min, they were sealed and irradiated for 120 h in a Rayonet reactor fitted with 300 nm lamps and a merry-go-round inset. The solvent was evaporated and purification by HPLC (cyclohexane/ethylacetate 93 7) yielded 0.352 g (41%) of 1.1.15c. 

Pyrolysis tube of quartz, /2/ Tube of duran glass (borosilicate), /3/ Sample boat of porcelain or corundum (50 x 8 x 6 ram), /A/ Gas flow controller to prevent back diffusion, /5/ Soft iron encased in quartz, for transport of the sample boat with a magnet, /6/ Tubular oven (1100 1150 C), / / Tubular oven (300 - 400°C), /8/ Asbestos sheet, /9/ Inlet for washing, /10/ To absorption vessel... 

Observe interface carefully if clear, re-extraction is not necessary (see Note 7). Remove phenol from bottom of tube using glass 5-mL pipet or Pasteur pipet and rubber pipet bulb or pipet pump. Do not worry about taking some of the aqueous layer. Pour off supernatants into Duran bottle of appropriate capacity. 

Experimental tests were carried out with irregular glass particles in order to compare both calibration techniques. The orifice tube selected was a 140 jum tube which was calibrated with a 20 jam nominal size latex (Coulter Electronics Ltd.) using the so called "half count method". For the mass calibration technique, a sieve fraction of the material under test, in the range of 37 44 tni, was used and a suspension of known concentration (4 8xl0 g/ / cm ) was carefully prepared. The density of the glass particles (Schott Duran 50) was measured to be 2.23 g/cm. ... 

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