摘要:
A method in which a pyridinium derivative such as 1,3-dimethyl-2,3-dihydro-2-oxopyrimidinium chloride is reacted with an acetyl compound such as 4-acetylpyridine, and then the reaction product is reacted with ammonia or an ammonium salt.
摘要:
A process has been found for preparing pyridine-2,6-diamines, i.e., 2,6-diaminopyridine (DAP) and derivative compounds in which one of the amino groups is a substituted amine (secondary or tertiary). According to this process, 3-hydroxy pentane 1,5-dinitrile (3-hydroxyglutaronitrile) is reacted with an ammonium donor in the form of ammonia, a primary amine such as n-butylamine, or a secondary amine such as piperidine.
摘要:
In a process for preparing 3-methylpiperidine or 3-methylpyridine from 2-methyl-1,5-diaminopentane in the gaseous phase, the initial product is made to flow over catalysts. In the first step, 3-methylpiperidine is produced, and if required 3-methylpyridine is produced in a second step.
摘要:
2,5-Disubstituted pyridines of the formula ##STR1## can be prepared by reacting enamines of the formula ##STR2## with .beta.-amino-acrylonitriles of the formula ##STR3## and treating the open-chain intermediate, which represents a R-R.sup.1 -5-amino-penta-2,4-dienonitrile, with protic acids or with ammonia.
摘要:
Process for the preparation of substituted pyridines by allowing 1-aza-1,3-butadienes to react, in the presence of a catalytic amount of secondary amine and acid, with an aldehyde or ketone, and new 1-aza-1,3-butadienes which are used in this process. Said pyridines can be obtained in high yield in a simple process with a short reaction time. The 1-aza-1,3-butadiene can, if so desired, be prepared in situ from an imine and an aldehyde.
摘要:
Process for the production of 2,4,6-trimethyl pyridine wherein acetone or an acetone derivative is reacted under pressure with ammonia in the presence of a metallic catalyst to form mixture of products with a high preparation of 2,4,6-trimethyl pyridine and recovering the trimethyl pyridine.
摘要:
A process for preparing pyridine or alkyl substituted pyridines in high yield, comprises reacting a C.sub.2-5 -aldehyde, a C.sub.3-5 -ketone or a mixture thereof, ammonia and, optionally, formaldehyde, in the gas phase in contact with a fluidized or otherwise movable bed of a catalytically effective amount of a crystalline aluminosilicate zeolite catalyst in the acidic form and having a constraint index of about 1 to about 12, with an actual contact time of the reactants with the catalyst which is at least as great as said actual contact time when the reaction is conducted in a 1 inch diameter fluid bed reactor with a pseudo contact time of at least about 2.5 seconds.
摘要:
Process for the production of 3,5-dialkylpyridines. An aldehyde having the formula R--CH.sub.2 --CHO, wherein R is a straight-chained or branched alkyl radical having 1 to 6 carbon atoms, and/or an acetal of such aldehyde is reacted with formaldehyde and/or hexamethylene tetramine and/or a formaldehyde acetal and/or a polymer of formaldehyde in liquid or aqueous phase at a temperature of 180.degree. to 280.degree. C. in a closed vessel in the presence of ammonia and/or ammonium ions and in the presence of anions of an inorganic and/or an organic acid, both of which at 20.degree. C. have an acid dissociation constant of 10.sup.6 to 10.sup.-12.
摘要:
The present invention relates to a process for the preparation of pyridine and substituted pyridines, in the vapor phase. These compounds are obtained by heating, at a temperature of 200.degree. to 500.degree. C., in the vapor phase:piperidine or piperidine substituted by one or more lower alkyl radicals;1,5-diaminopentane;1,5-diaminopentane containing, in its hydrocarbon part, from 1 to 3 linear or branched alkyl radicals having from 1 to 4 carbon atoms; orcompounds such as: N,N'-bis-(piperidin-2-yl)hydrazines,in the presence of a catalyst consisting of palladium, platinum or ruthenium deposited on a macroporous solid.The products obtained by the process according to the invention have various uses. Pyridine is used in particular as a solvent. .beta.-Picoline (or 3-methylpyridine) is used for the preparation of nicotinic acid or nicotinamide, used in pharmacy and in nutrition.
摘要:
Alpha-picolines are produced by containing aniline or substituted anilines, such as alkyl-, cyclo alkyl-, halo- ; alkoxy- or substituted alkyl-anilines with a crystalline zeolite catalyst having a silica:alumina ratio of at least 12 and a constraint index of 1 to 12. ZSM-5 type catalysts are contacted at elevated temperature to yield alpha-picolines selectively.