Parr hydrogenation bomb

A solution of 3.5 g 2,3-methylenedioxy-6-nitro-beta-dimethylaminostryrene in 200 ml benzene was placed in a Parr hydrogenation bomb and treated with 0.35 g of 10% Pd / C. The mixture was shaken for 7 h under 3 atm H2. The catalyst was removed by filtration, and the filtrate was washed first with 2N H2S04, followed by aqueous NaHC03 and H20. This was dried and the solvent removed under vacuum to give 1.2 g (50%) of 4,5-methylenedioxyindole as a residue. After crystallization from benzene / petroleum ether, it had a mp 111 °C. Anal C,H,N. 

A solution of 3.5 g 2,3-methylenedioxy-6-nitro-beta-dimethyl-aminostryrene in 200 mL benzene was placed in a Parr hydrogenation bomb and treated with 0.35 g of 10% Pd/C. The mixture was shaken for 7 h under 3 atm H2. 

A mixture of 126 g. (1.50 moles) of dimethylaminoacetonitrile (p. 124) and 30 g. of Raney nickel catalyst [Org. Syntheses, 21, 15 (1940) ] is placed in a Parr hydrogenation bomb and a tated at around 1000 lb. hydrogen pressure and a temperature of 78°. The theoretical amount of hydrogen is absorbed in about 3 hours. The catalyst is removed by filtration, and the filtrate is fractionally distilled. There is obtained 62 g. (47%) of j8-dimethylaminoethylamine, boiling at 105-108° at atmospheric pressure. 

Dtatmno-l-alkenes. Doss Bost (Ref 1) describe the prepn of 1, 2-bis(dimethyl-amino) ethylene (bp 38-40° at 15mm l, s 4648), its hydrogenation in a Parr bomb at 40lb/sq inch to the ethane (nfi 1.4170) and the use of the ethane deriv as a component of hypergolic fast-burning rocket fuels... 

The AH° of reaction at 298.16° K. of oxygen difluoride with hydrogen was measured using a Parr fluorine combustion bomb modified to contain a metal ampoule employing a burst diaphragm. This modification permits heat of reaction measurements on systems where reaction occurs spontaneously upon mixing the reactants. The AH° of the reaction OFt - HtO + 2HF (infinite dilution) was found... 

A complete and reliable analysis has shown our earlier conclusion concerning the oxyfluoride to be incorrect and has proved the empirical formula to be F,0,Pt (Found F, 32-4 O, iO-4 Pt, 57-5. F,0,Pt requires F, 33-4 O, 9-4 Pt, 57-2%). Fluorine was determined by a modified pyrohydrolytic method, and platinum by ignition in hydrogen of the hydroxide produced in the hydrolysis. Independent analysis was made for platinum by ignition of the solid in hydrogen (Found Pt, 57-4 %) and for fluorine by fusion of a sample with sodium in a Parr bomb (Found F, 327%). Oxygen was determined by displacement of the gas with bromine trifluoride. 

In an attempt to prepare polycyclopentadiene which would be stable in toluene solution, the polymer was hydrogenated over a platinum oxide catalyst in a Parr bomb immediately after the completion of the polymerization reaction. Infrared analysis indicated the presence of residual unsaturation and the polymer became insolubilized on standing. An attempted copolymerization of cyclo-pentadiene with propylene gave a product whose infrared spectrum indicated the presence of C-methyl groups but which was still insoluble in toluene. No attempt was made to determine whether copolymerization had occurred. 

The nitro precursors above were dissolved in DMAc and hydrogenated to the desired monomers in a Parr bomb at 50-55°C and at an initial pressure of about 60 psi. After evaporation of DMAc on a rotary evaporator, the products were recrystallized from ethanol in 95% yield. 

Parr bombs used for hydrogenations should be handled with care behind a shield, and the operator should wear goggles and a face shield. 

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