摘要:
A process for the preparation of 2,6-dimethylmorpholine from N-(2-hydroxypropyl)-2,6-dimethylmorpholine, in which N-(2-hydroxypropyl)-2,6-dimethylmorpholine, in whicha) N-(2-hydroxypropyl)-2,6-dimethylmorpholine is caused to react in the presence of a catalyst containing an element listed in Groups Ib, IIb, and/or VIIIb of the Periodic Table at temperatures ranging from 150.degree. to 600.degree. C. and is then caused to react with water at temperatures ranging from 30.degree. to 300.degree. C. orb) N-(2-hydroxypropyl)-2,6-dimethylmorpholine is caused to react in the presence of an acid catalyst at temperatures ranging from 100.degree. to 400.degree. C. followed by acid hydrolysis with water at temperatures ranging from 30.degree. to 300.degree. C.
摘要:
A process for the preparation of N-(2-hydroxypropyl)-2,6-dimethylmorpholine, wherein tris-(2-hydroxypropyl)amine is cyclizeda) in the presence of acid catalysts orb) in the presence of hydrogenation catalysts.
摘要:
Pyrazole and its derivatives are prepared by dehydrogenating 2-pyrazoline or its derivatives by a process in which the reaction is carried out using sulfuric acid in the presence of iodine or of an iodine compound at from 50.degree. to 250.degree. C.
摘要:
A process for preparing pyrazole and its derivatives of the formula I ##STR1## where R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each hydrogen, halogen, nitro, carboxyl, sulfonyl or C-organic radicals, from alpha,beta-unsaturated carbonyl compounds of the formula II ##STR2## and hydrazine or hydrazine derivatives of the formula IIIH.sub.2 N--NHR.sup.4 IIIwherein, initially without additional diluent, an alpha,beta-unsaturated carbonyl compound of the formula II is reacted with hydrazine or a hydrazine derivative of the formula III, and the resulting reaction mixture is reacted in another step with a mixture of sulfuric acid and iodine or a compound which liberates iodine or hydrogen iodide.
摘要:
N-substituted-pyrazoles of the formula ##STR1## wherein R.sup.1 is C.sub.1 -C.sub.12 -alkyl or C.sub.7 -C.sub.20 -alkyl, and R.sup.2, R.sup.3 and R.sup.4 independently denote hydrogen, C.sub.1 -C.sub.12 -alkyl, phenyl, C.sub.7 -C.sub.20 -alkylphenyl and C.sub.7 -C.sub.20 -phenylalkyl, are prepared by reacting a pyrazole of the formula ##STR2## wherein R.sup.2, R.sup.3 and R.sup.4 have the meanings above, with an alcohol or ether of the formulaR.sup.1 --O--R.sup.5 III,wherein R.sup.5 is hydrogen or R.sup.1, at a temperature of from 200.degree. to 550.degree. C. and a pressure of from 0.001 to 50 bar in the presence of a heterogeneous catalyst, preferably one which contains acid centers such as the oxides of aluminum, silicon, titanium and/or zirconium, optionally doped with phosphoric acid.
摘要:
3-Methylpyrazole and its derivatives are prepared by reacting butenediols or ethynylalkylcarbinols or their acylates in 30-100% by weight sulfuric acid with unsubstituted or substituted hydrazine or its salts in the presence of catalytic amounts of iodine or an iodine compound.