Drying with argon

When necessary, 6 mol% of PEG-PE and 1 mol% of DTPA-S A are added to the lipid mixture, which is then dried with argon, further dried under vacuum, then solubilized with OG in HEPES-buffered saline (HBS), pH 7.4 (final total lipid concentration may vary from 5 to 20 mg/mL), and dialyzed overnight against HBS at 4°C. 

After synthesis, the CPG column is removed from the synthesizer and dried with argon. The CPG support is removed, placed in a 1-dram vial, and ethanolic ammonia (850 pL), and benzene (150 pL) are added. The vial is sealed with a Teflon -lined screw cap, allowed to remain at rt for 1 h, and then placed in a 55°C oven for 15 h. After removal from the oven and cooling to rt, toluene (2 mL) is first added, and the combined solution carefully removed from the CPG support by pipeting. This solution contains traces of DNA and nearly all of the benzamide. Water (1 mL) is then added to the vial containing the CPG in order to extract the dithioate DNA from the support. In the case of purine-rich sequences, water acetonitrile (3 1) is a better solvent for the oligomers. 

Bromo-3-iodo-l-(4-methylphenylsulfonyl)indole (0.476 g, 1.00 mmol), methyl acrylate (0.108 g, 1.25 mmol), EtjN (0.127 g, 1.25 mmol) and Pd(OAc)2 (11 mg, 0.050 mmol) were mixed in a tube, purged with argon and the tube was sealed and heated to 100°C for 1 h. After cooling, it was opened and mixed with CH2CI2 (50 ml). The solution was washed with water and dried (Na SOJ. The residue was purified by chromatography on silica using 1 3 benzene-hexane for elution. The yield was 0.350 g (81%). 

A dry 1-L, three-necked, round-bottomed flask equipped with a large Teflon-covered magnetic stirring bar, a thermometer, and a dry ice condenser (Note 1) is flushed with argon (Note 2), then capped with a serun stopper and subsequently maintained under a positive pressure of argon (Note 3). A 30 dispersion of lithium metal (in mineral oil) containing 1% sodium (13.9 g, 2.00 g-atom of lithium) (Note 4) is rapidly weighed and transferred to the flask. 

The reaction is carried out under argon in a 2-liter three-necked flask fitted with a mechanical stirrer, reflux condenser, 250-ml pressure-equalizing addition funnel, and gas inlet and outlet. After purging with argon, the flask is charged with a solution of 89 g (0.48 mole) of ferrocene in 1 liter of dry tetrahydrofuran. The solution is next heated to 45°, and there is added dropwise with stirring, 155 ml (0.29 mole) of an -butyllithium solution (15% in heptane-pentane, 2 1, Foote Mineral Co.) during a period of 75 minutes. The resultant solution is maintained at 45° for an additional 2 hours, then is cooled to —77° by means of an external Dry Ice-chloroform bath. 

Via the Z-enolate an oven dried Schlenk tube equipped with a rubber septum is flushed with argon and charged with 0.66 mL (1.0 mmol) of butyllithium (1.5 N in hexane). The Schlenk tube is cooled to 0°C (icc/salt) and 0.12 g (1.1 mmol) of diisopropylaminc are added slowly by a syringe. This mixture is stirred for 15 min and the rubber septum is replaced by a glass stopper. The hexane and the excess diisopropyl-amine are removed under reduced pressure. After the flask is filled with argon the stopper is replaced with a septum and 0.47 g (4.3 mmol) of HMPA and 2.5 mL of THF are added. This solution is immediately cooled to — 78 °C and 0.14 g (1.1 mmol) of tert-butyl propanoate arc added quickly by syringe. After stirring for... 

A. (E)-l-Propenyllithium. A dry (Note 2), 500-ml., three-necked, round-bottomed flask equipped with a Teflon -covered magnetic stirring bar, a 200-ml. pressure-equalizing dropping funnel, an efficient reflux condenser, and an immersion thermometer is capped with serum stoppers (Note 3) and flushed with argon (Note 4). Lithium dispersion (Note 5), [22.4 g. of a 50% wjw suspension in Amseo,... 

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