Distillation fume hood

Vote 1. The distillation should therefore be conducted in a fume hood. 

O. 93. Dry with Na2S04, and distil as rapidly as possible under vacuum to avoid decomposition. Discard fractions boiling below 78-82 / 5mm. Store in the dark. USE AN EFFICIENT FUME HOOD as HCN (POISONOUS) is always present. [Org Synth Col.Vol. II 7 1940.]... 

Butyryi chloride (butanoyl chloride) [141-75-3] M 106.6, f -89°, b 101-102°/atm, 1.026, Hp 1.412. Check IR to see if there is a significant peak at 3000-3500 cm (br) for OH. If OH is present then reflux with less than one mol equiv of SOCI2 for Ih and distil directly. The fraction boiling between 85-100° is then refractionated at atm pressure. Keep all apparatus free from moisture and store the product in sealed glass ampoules under N2. LACHRYMATORY - handle in a good fume hood. [Org Synth Coll Vol I 147 794/.]... 

Set the 250-mL beaker in place on the platform of the distillation apparatus in the fume hood such that the glass tip of the condenser is under the surface of the solution in the beaker. Make sure that the stopcock on the upper left of the distillation unit (the addition stopcock) is closed. Also make sure that the other stopcock (the siphon stopcock) is closed. Add the contents of the Kjeldahl flask to the funnel above the addition stopcock. Open this stopcock to deliver the solution fairly... 

Assemble a boiling water bath in a fume hood using a hot plate and a 250-mL beaker filled halfway with distilled water. 

The required amount of HCN was freshly distilled in a well-ventilated fume hood. Sodium cyanide (128 g) was dissolved in deionized water (320 mL) and 5 m sulfuric acid (320 mL) was added dropwise within the distillation equipment and the resulting solution was heated up to 75 °C. The hydrogen cyanide was condensed immediately in a receiving flask cooled to 5 °C. Total yield of hydrogen cyanide 68 mL. 

The use of distilled formaldehyde, not formalin, which contains alcohol, is recommended. Freshly prepared paraformaldehyde can also be used, especially if large volumes of fixative are needed for perfusion fixation. To prepare an 8% solution of paraformaldehyde, in a fume hood add 2 g of paraformaldehyde (trioxymethylene) powder to 25 mL of deionized glass-distilled water. With constant stirring, heat solution to 60-70°C. Once the solution has reached the proper temperature, continue to stir for 15 min. The solution will be milky. Add one to two drops of 1 VNaOH, with stirring, until the solution clears. A slight miUdness may persist. Cool and filter through Whatman No. 1 filter paper. This solution should be used the same day that it is prepared. 

Caution 2-Diazocyclohexanone may explode, especially on being heated. The worlcup and distillation should be carried out in a fume hood behind a safety shield. 

Acetyl chloride was purchased from the Acros Chimica and distilled before use. The checkers purchased acetyl chloride from Aldrich Chemical Company, Inc., and used it without purification. Caution Acetyl chloride is a reactive substance that must be handled in a fume hood. 

Caution. Tetrahydrofuran is extremely flammable and forms explosive peroxides only freshly distilled, peroxide-free material should be used. Lithium-dispersion is a hazardous material and must be handled in dry conditions and under an inert gas atmosphere. Trimethylchlorosilane and trichloromethylsilane can cause severe skin and eye burns. All manipulations should be carried out in a well-ventilated fume hood protective gloves and safety glasses should be worn. 

Caution. DMEAA is air-sensitive and inflames upon contact with water. All the reactions are performed under an inert atmosphere. In the synthesis of DMEAA, it is crucial to remove all the aluminum particles from the reaction solution by filtration after the reaction is complete. The aluminum particles remaining from the incomplete filtration can cause autocatalytic and exothermic gas-evolving decomposition of DMEAA which may lead to an explosion. Also, the product should not be overheated during the vacuum distillation. For disposal, DMEAA should be diluted with heptane and allowed to react slowly with isopropyl alcohol with cooling in a fume hood. 

CNBr (toxic and may produce toxic gas carry out all steps in an efficient fume hood) Dissolve the whole bottle to make a 100 mg/mL stock in distilled water, and store in a well-sealed bottle at -20°C. 

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