摘要:
The present invention relates to a multi-stage process for producing substituted, optically active alcohols, comprising an enzyme-catalyzed synthesis step, in particular a synthesis step which is catalyzed by an alcohol dehydrogenase. The inventive method is particularly suitable for producing phenylephrine, i.e. 3-[(1R)-1-hydroxy-2-methylamino-ethyl]-phenol.
摘要:
The present invention relates to a multi-stage process for producing substituted, optically active alcohols, comprising an enzyme-catalyzed synthesis step, in particular a synthesis step which is catalyzed by an alcohol dehydrogenase. The inventive method is particularly suitable for producing phenylephrine, i.e. 3-[(1R)-1-hydroxy-2-methylamino-ethyl]-phenol.
摘要:
A process for preparing O-alkylated amino alcohols by reacting N-unsubstituted or N-monosubstituted amino alkoxide salts with alkyl halides, the amino alkoxide salts being formed by means of alkali metal or alkaline earth metal hydroxides.
摘要:
Diastereoselective conversion of chiral imines of the formula I to amines of the formula II where the R1 to R4 radicals are each as defined in the description and R1 and R2 are different than one another, by converting the imine of the formula I in the presence of hydrogen and a heterogeneous copper-containing catalyst.
摘要:
A method for producing 3-pentenenitrile is provided that includes: (a) isomerizing an educt stream containing 2-methyl-3-butenenitrile on at least one dissolved or dispersed isomerisation catalyst to form a stream (1), which contains the isomerisation catalyst(s), 2-methyl-3-butenenitrile, 3-pentenenitrile and (Z)-2-methyl-2-butenenitrile; (b) distilling the stream (1) to obtain a stream (2) as the overhead product, which contains 2-methyl-3-butenenitrile, 3-pentenenitrile and (Z)-2-methyl-2-butenenitrile and a stream (3) as the bottom product, which contains the isomerisation catalyst(s); (c) distilling the stream (2) to obtain a stream (4) as the overhead product, which is enriched with (Z)-2-methyl-2-butenenitrile in comparison to stream (2), and a stream (5) as the bottom product, which is enriched with 3-pentenenitrile and 2-methyl-3-butenenitrile in comparison to stream (2); (d) distilling stream (5) to obtain a stream (6) as the bottom product, which contains 3-pentenenitrile and a stream (7) as the head product containing 2-methyl-3-butenenitrile.
摘要:
The present invention relates to a process for preparing pentamethylene 1,5-diisocyanate, to pentamethylene 1,5-diisocyanate prepared in this way and to the use thereof.
摘要:
The invention provides metal carbamates of the general formula (I) where R1 and R2 are the same or different and are each an alkyl group having 1-18 carbon atoms and M is an alkali metal atom.
摘要:
The invention relates to a process for obtaining a pure aliphatic dialdehyde monoacetal by reaction of the corresponding aliphatic dialdehyde or a precursor of the corresponding aliphatic dialdehyde with one or more aliphatic mono- or polyhydric alcohols while distillatively removing water to obtain a reaction mixture which is separated distillatively, which comprises carrying out the distillative separation continuously in a dividing wall column to obtain pure aliphatic dialdehyde monoacetal as a sidestream from the dividing wall column, or in two distillation columns to obtain crude aliphatic dialdehyde monoacetal as a sidestream in the first distillation column, feed the crude aliphatic dialdehyde monoacetal to the second distillation column and obtain pure aliphatic dialdehyde monoacetal as the sidestream from the second distillation column.
摘要:
A system comprising a) Ni(0) b) from 4 to 10 mol per mol of Ni(0) in a) of a compound (I) of the formula P(X1R1)(X2R2)(X3R3) (I) where X1, X2, X3 are each, independently of one another, oxygen or a single bond, R1, R2, R3 are, independently of one another, identical or different organic radicals and c) from 1 to 4 mol per mol of Ni(0) in a) of a compound (II) of the formula where X11, X12, X13 X21, X22, X23 are each, independently of one another, oxygen or a single bond, R11, R12 are identical or different, individual or bridged organic radicals, R21, R22 are identical or different, individual or bridged organic radicals and Y is a bridging group is suitable as catalyst for preparing mixtures of monoolefinic C5 mononitriles having nonconjugated C═C and C═N bonds by hydrocyanation of a 1,3-butadiene-containing hydrocarbon mixture and for preparing a dinitrile by hydrocyanation of a mixture of monoolefinic C5 mononitriles having nonconjugated C═C and C═N bonds.
摘要翻译:一种系统,其包含a)式(I)中的式(ⅰ)中的每一摩尔Ni(0)中的Ni(0)b)4至10摩尔的式(ⅰ)的线性式描述=“在线式” 结束=“铅”→P(X 1> 1 SUP>)(X 2 2 R 2)(X (I)<?in-line-formula description =“In-line Formulas”end =“tail”?>其中X <1> X 2,X 3,X 3各自彼此独立地为氧或单键,R 1,R 2, > 2,R 3彼此独立地为相同或不同的有机基团,c)1至4摩尔每摩尔a)化合物中的Ni(0) II),其中X 11,X 12,X 13,X 21,X 22 X 23,X 23各自彼此独立地为氧或单键,R 11,R 12和R 12相同或相同, 不同的单个或桥连的有机基团,R 21,R 22和R 22相同或不同,单个或桥接的有机基团和 Y是桥联基团,适合作为通过含1,3-丁二烯的烃混合物的氢氰化制备具有非共轭CC和CN键的单烯键式C 5 H 5单体的混合物的催化剂,并通过氢氰化制备二腈 的具有非共轭CC和CN键的单烯烃C 5 H 5单体的混合物。