Stirring in an inert atmosphere

Mercury-sealed stirrers are used in the following operations (1) simultaneous stirring and refluxing of a reaction mixture (2) stirring the contents of a closed vessel (3) agitation with prevention of the escape of a gas or vapour and (4) stirring in an inert atmosphere, such as... 

AH was prepared in the usual manner from a suspension of 2.0 g LAH in 75 mL anhydrous THF, cooled to 0 °C and well stirred in an inert atmosphere of He, and treated with 1.33 mL of 100% H2S04 added dropwise. There was added, drop-wise and over the course of 10 min, a solution of 3.1 g 3-ethylthio-4,5-dimethoxy-B-nitrostyrene in 15 mL anhydrous THF. At the end of the addition, the reaction mixture was returned to room temperature, and finally heated on the steam bath for 10 min. After cooling again, there was added enough IPA to decompose the excess hydride and sufficient 10% NaOH to convert the aluminum oxide to a white, easily filterable mass. This was removed by filtration, the filter cake washed with additional IPA, and the filtrate and washes combined and the solvent removed under... 

A 160 ml solution of potassium naphthalide (67 mg naphthalene, 20 mg potassium) is titrated under stirring in an inert atmosphere and room temperature with a solution of monohydroxy poly(ethylene glycol) of molecular weight 5,000 (1 g, 0.2 mmol) in freshly distilled tetrahydrofiiran (5 ml) until the typical dark green colour disappears. 

AH was prepared in the usual manner from a suspension of 3.0 g LAH in 100 ml anhydrous THF, cooled to 0 deg C, well stirred in an inert atmosphere of He, and treated with 2.0 ml of 100% H2S04 added dropwise. There was then added a solution of 2.4 g... 

A suspension of 7.5 grams LAH in 500ml anhydrous Et20 was magnetically stirred, and heated in an inert atmosphere to a gentle reflux. The condensing Et20 leached out a total of 9.8 g 2-nitro-... 

The triethoxysilapropylisocyanide was prepared as outlined in reference 7, and characterized by its lH, 13C NMR, IR and mass spectra. For details see reference 1A. Aqueous NaOH [0.09 g in 3 ml H2O] was added dropwise to a mixture of 30 ml [0.17 mole] of (Et0)2SiMe2 and 2.5 ml [0.01 mole] of (EtO)3Si(CH2)3NC. The solution was stirred under an inert atmosphere for 2A hr. in the dark at room temperature. After completion of the reaction, the residue was washed thoroughly with water until neutral. It was then resuspended in hexane and dried over MgSO for several hours. The solution was decanted, the... 

If 13 was allowed to stand at room temperature in an inert atmosphere over a prolonged period, or if a saturated hexane solution of Cp2TiMe2 was treated with excess hydrogen at low temperature with efficient stirring, a gray-green polymeric titanocene hydride 14 formed which exhibited reactivity similar to the violet hydride 13 (24). Thus, exposure of a toluene... 

If mechanical degradation of a polymer solution by high speed stirring is carried out with a vinyl monomer in an inert atmosphere the monomer will be polymerized by the free macroradical. Goto and Fujiwara, for example, studied poly(vinyl acetate vinyl acetate) agitated in an Homomixer at 30000 rpm in a nitrogen atmosphere at 65° C (99). They found that the polymerization rate, Vp, is proportional to the square root of the initial concentration of poly(vinyl acetate) ... 

CiystaHine 100% orthophosphoric acid (40 g, 0.41 mol) and [Et4N][V(CO)6] (6.0 g, 17.2 mmol) were intimately mixed together in an inert-atmosphere box at room temperature in a 500-mL round-bottom flask equipped with a large Teflon-coated magnetic stirring bar. The flask is attached to a connecting tube and a specially adapted Schlenk tube receiver as shown in Fig. 1. 

A solution of 2.0 g N-ethyl-N-isopropylindol-3-ylglyoxylamide in 50 mL anhydrous THF was added, dropwise, to 1.5 g LAH in 50 mL anhydrous THF which was well-stirred under an inert atmosphere. This was brought to reflux and held there for 3 h. The reaction mixture was cooled, and the excess hydride destroyed by the cautious addition of wet THF. A 15% NaOH solution was then added until the solids had a loose white cottage cheese character to them, and the mobile phase tested basic by external damp pH paper. These formed solids were removed by filtration, washed first with THF and then MeOH. The filtrate and washings were combined, dried over anhydrous MgS04, and the solvent removed under vacuum. The residue set up to a crystalline mass weighing 1.6 g (90%). This was recrystallized from pentane to provide N-ethyl-N-isopropyltryptamine (EIPT) as a free base with a mp of 71-73°C. Indole can also serve as a precursor to NET which is easily transformed into EIPT. 

A suspension of 0.5 g LAH in 10 mL anhydrous THF was held in an inert atmosphere and vigorously stirred. To this there was added, dropwise, a solution of 0.6 g of 4-acetoxyindol-3-yl-N,N-diethylglyoxylamide in 10 mL anhydrous THF at a rate that maintained a gentle reflux. After the addition was complete, the refluxing was maintained for an additional 15 min, cooled to 40... 

To 10 mL of a stirred solution of LAH (1 M in THF under N2), there was added dropwise a solution of 600 mg 4-acetoxy-N-methyl-N-isopropylindole-3-glyoxylamide in 10 mL anhydrous THF. When the addition was complete, the reaction mixture was brought to a reflux on the steam bath for 15 min. After cooling to 40 °C, sufficient water was added to decompose both the reaction complex and the excess hydride. After filtration through Celite (under an N2 atmosphere), the solvent was removed under vacuum, and the solid residue recrystallized from /hexane. There was thus obtained 340 mg (74%) of 4-hydroxy-N-methyl-N-isopropyltryptamine (4-OH-MIPT) with a mp of 123-124 °C. 4-HO-MIPT discolors quickly if it is not kept in an inert atmosphere and in a freezer. Anal C,H,N. 

A suspension of 0.76 g LAH in 50 mL THF was stirred under an inert atmosphere, and treated with the dropwise addition of a solution of 2.5 g N-(benzyloxycarbonyl)-4-methoxytryptamine in 30 anhydrous THF. The reaction mixture was held at reflux for 30 min, then cooled to 40 °C and the excess hydride destroyed with the addition of 50% aqueous THF. The solids were removed by filtration, washed with THF, the filtrate and washings combined, and the solvent removed under vacuum. The residue, impure 4-methoxy-N-methyltryptamine, was dissolved in 50 mL ethanol, treated with 1.0 mL acetone, then with 0.5 g 10% Pd / C, and the reaction mixture shaken under a hydrogen atmosphere at 50 psi for 15 h. The catalyst was removed by filtration through a bed of Celite, the filtrate stripped of solvent under vacuum, and the solid residue recrystallized from Et20 / hexane to give 0.51 g 4-methoxy-N-methyl-N-isopropyltryptamine (4-MeO-MIPT) which had a mp 80-81 °C. Anal C15H22N20. C,H,N. MS (in m/z) C5H12N+ 86 (100%) indolemethylene+ 160 (4%) parent ion 246 (6 %). 

A suspension of 1.5 g LAH in 150 mL of warm anhydrous THF was stirred under an inert atmosphere and brought up to a gentle reflux. A solution of 2.3 g 1 -(2,5-dimethoxy-4-(n)-propylthiophenyl)-2-nitropropene in 25 mL anhydrous THF was added dropwise at a rate that maintained the reflux. Heating and stirring were continued for 2 days, and then the reaction mixture was allowed to stir at room temperature for an additional 2 days. There was added 1.5 mL Hp (dissolved in... 

Fifty milliliters of 1 M LAH in THF was placed in an inert atmosphere, well stirred, and cooled to 0 °C with an external ice-bath. There was added, dropwise, 1.35 mL of 100% H2S04 at a rate slow enough to minimize charring. There was then added, dropwise, 2.8 g l-(2,5-dimcthoxy-3,4-(trimethylene)phenyl)-2-nitropropene in 15 mL THF. At the end of the addition, the stirring was continued for an additional 0.5 h, and then the reaction mixture was held at reflux on the steam... 

SYNTHESIS A solution of 5.50 g 2,5-dimethoxy-4-ethylthio-B-nitrostyrene (see under 2C-T-2 for its preparation) was made in 80 mL boiling anhydrous THF. On cooling, there was some separation of a fine crystalline phase, which was kept dispersed by continuous stirring. Under an inert atmosphere there was added 3.5 mL of a 10 M borane dimethylsulfide complex, followed by 0.5 g sodium borohydride as a solid. There was a slight exothermic response, and the color slowly faded. Stirring was continued for a week. There was then added 40 mL H,0 and 20 mL... 

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