Distillation distn vacuum

Di-n-butyl boron triflate (di-n-butylboryl trifluorosulphonate) [60669-69-4] M 274.1, b 37°/0.12mm, 60°/2mm. Distil in vacuum under argon and store under argon. Should be used within 2 weeks of purchase or after redistn. Use a short path distn system. It has IR bands in CCI4 at v 1405, 1380, 1320, 1200 and 1550cm- and 3c NMRfCDCb) with 8 at 118.1, 25.1, 21.5 and 13.6ppm. [Org Synth 68 83 7990 JACS 103, 3099 7957]. 

To save space the following abbreviations have been generally used in Chapters 3, 4 and 5 abs (absolute), anhyd (anhydrous), aq (aqueous), atm (atmospheric), crystd (crystallised), crystn (crystallisation), crysts (crystallises), dec (decomposes), dil (dilute), distd (distilled), distn (distillation), evap (evaporate), evapd (evaporated), evapn (evaporation), filtd (filtered), h (hour[s]), pet ether (petroleum ether, ligroin), ppte (precipitate), ppted (precipitated), pptn (precipitation), satd (saturated), soln (solution), TLC (thin layer chromatography), HPLC (high pressure liquid chromatography), vac (vacuum), vol (volume). Other abbreviations used occasionally are self evident in meaning. 

Titles of periodicals are defined as in the Chemical Abstracts Service Source Index (CASSI), except that full stops have been omitted after each abbreviated word. Abbreviations of words in the texts of Chapters 4, 5 and 6 are those in common use and are self evident, e.g. distn, filtd, cone and vac are used for distillation, filtered, concentrated and vacuum. 

Conductivity grade benzonitrile (specific conductance 2 x 10" mho) was obtained by treatment with anhydrous AICI3, followed by rapid distn at 40-50° under vacuum. After washing with alkali and drying with CaCl2, the distillate was vac distd several times at 35° before being fractionally crystd several times by partial freezing. It was dried over finely divided activated alumina from which it was withdrawn as required [Van Dyke and Harrison J Am Chem Soc 73 402 7957]. 

Bromoindole [10075-50-0] M 196.1, m 90.5-91°, 90-92°, pK 16.13 (NH). Purified by steam distn from a faintly alkaline soln. Cool the aqueous distillate, collect the solid, dry in a vacuum desiccator over P2O5 and recryst from aqueous EtOH (35% EtOH) or pet ether-Et20. MeOH 279, 287 and 296 (loge... 

Vacuum distn at 60-65°/15mm, discarding the first 5-10%, was followed by dilution with an equal volume of freshly distilled water at 70-75°, using magnetic stirring under nitrogen. The soln is stored at low temp (3-4°),... 

M HCI). Crystd from aqueous 70% EtOH. Dehydrated by vacuum distn, the distillate being allowed to crystallise in a vacuum to prevent the uptake of CO2 and water vapour. The anhydrous base was then recrystd from dry ether [Fleming and Saunders JCS 4150 7955]. 

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