Schlenk and glovebox techniques

Vacuum-lines, Schlenk and Glovebox Techniques. Manipulations involving materials sensitive to air or water vapour can be carried out by these procedures. Vacuum-line methods make use of quantitative transfers, and P(pressure)-V(volume)-T(temperature) measurements, of gases, and trap-to-trap separations of volatile substances. 

Syringe techniques have been worked out for small volumes, while for large volumes or where much manipulation is required, dryboxes (glove boxes) or dry chambers should be used. 

For fuller discussion, see Sanderson Vacuum Manipulation of Volatile Compounds John Wiley and Sons Ltd, NY, 1948 L.W.Muller Vacuum Technology Principles and Applications, Chapman Hall Ltd, 1995 W.H.Kohl Handbook of Materials Techniques for Vacuum Devices, American Institute of Physics Press, 1994 Shriver The Manipulation of Air-sensitive Compounds McGraw-Hill Book Co, NY, 1969 Brown Organic Syntheses via Boranes, Wiley, NY, 1975 A.Pelter Borane Reagents, Academic Press Inc., 1988. 

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. 

TABLE 1. SOME COMMON IMMISCIBLE OR SLIGHTLY MISCIBLE 

Carbon tetrachloride with ethanolamine, ethylene glycol, formamide or water. 

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All manipulations are performed under argon or dry nitrogen using standard Schlenk and glovebox techniques. Phosphines (Strem), cyclopentadienylirondi-carbonyl dimer, and tetrafluoroboric acid (Aldrich) are commercial samples used as received. 

All experiments are to be carried out in a well-ventilated fume hood. The imperative exclusion of air and moisture is ascertained by the appropriate Schlenk and glovebox techniques. Solvents are dried by distillation from sodium/benzophenone (dme) or potassium (hexane) and degassed by three pump—freeze—thaw cycles prior to use. All glass equipment is stored at 120°C overnight, assembled and subjected to at least two cycles of evacuation and refilling with argon while still hot. 

All manipulations performed under a dry N2 atmosphere using standard Schlenk, syringe, and glovebox techniques.7 Solvents are distilled under N2... 

All manipulations of compounds were carried out using standard Schlenk, vacuum line, and glovebox techniques. Pentane, diethyl ether, tetrahydrofuran, and toluene... 

Since silylenes are air and moisture sensitive, the synthetic operations were carried out under an atmosphere of dry argon or nitrogen by using modified Schlenk line and glovebox techniques. Solvents THF and toluene were freshly distilled from sodium... 

These limitations were overcome with the introduction of the well-defined, single-component tungsten and molybdenum (14) alkylidenes in 1990. (Fig. 8.4).7 Schrock s discoveiy revolutionized the metathesis field and vastly increased die utility of this reaction. The Schrock alkylidenes are particularly reactive species, have no side reactions, and are quite effective as polymerization catalysts for both ROMP and ADMET. Due to the oxophilicity of molybdenum, these alkylidenes are moisture and air sensitive, so all reactions using these catalysts must be performed under anaerobic conditions, requiring Schlenk and/or glovebox techniques. 

Reactions were conducted under N2 using glovebox and Schlenk techniques conditions and analytical methods are described in Tables and text. See also ref. 1 for details of how hydration yields were determined by NMR. 

All manipulations were performed under a nitrogen atmosphere by standard Schlenk techniques or in a glovebox maintained at or below 1 ppm of 02 and... 

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