Highly Efficient Heterogeneous Gold-catalyzed Direct Synthesis of Tertiary and Secondary Amines from Alcohols and Urea
作者:Lin He、Yue Qian、Ran-Sheng Ding、Yong-Mei Liu、He-Yong He、Kang-Nian Fan、Yong Cao
DOI:10.1002/cssc.201100581
日期:2012.4
Urea, the white gold: The efficientsynthesis of tertiary and secondaryamines is achieved by heterogeneous gold‐catalyzed direct amination of stoichiometric alcohols with urea in good to excellent yields. Via a hydrogen autotransfer pathway, the reactions of primary alcohols with urea give tertiaryamines exclusively, while secondaryalcohols selectively afford secondaryamines.
Ruthenium-catalyzed Formation of Tertiary Amines from Nitriles and Alcohols
作者:Saiwen Liu、Ru Chen、Guo-Jun Deng
DOI:10.1246/cl.2011.489
日期:2011.5.5
A ruthenium-catalyzed tertiary-amine formation was developed using the borrowing hydrogen strategy. Various tertiaryamines were obtained efficiently fromnitriles and primary alcohols. Two possibl...
使用借氢策略开发了钌催化的叔胺形成。从腈和伯醇中可以有效地获得各种叔胺。两种可能...
The “Borrowing Hydrogen Strategy” by Supported Ruthenium Hydroxide Catalysts: Synthetic Scope of Symmetrically and Unsymmetrically Substituted Amines
the N‐alkylation of ammonia (or its surrogates) and amines with “primary” alcohols. On the other hand, the N‐alkylation of ammonia surrogates (i.e., urea and NH4HCO3) with “secondary” alcoholsselectively produced the corresponding symmetrically substituted “secondary” amines, even in the presence of excess amounts of alcohols, which is likely due to the steric hindrance of the secondary alcohols and/or
易于制备的厌氧条件下,可以有效地促进氨(或其替代物,如尿素,NH 4 HCO 3和(NH 4)2 CO 3)和胺与醇(包括伯醇和仲醇)的N-烷基化反应。廉价的负载型氢氧化钌催化剂Ru(OH)x / TiO 2。氨(或其替代物)和胺与“伯”醇的N烷基化反应可以合成各种类型的对称和不对称取代的“叔”胺。另一方面,氨代用品(即尿素和NH 4)的N烷基化HCO 3)与“仲”醇选择性地产生相应的对称取代的“仲”胺,即使在存在过量的醇的情况下,这很可能是由于所产生的仲醇和/或仲胺的空间位阻所致。在有氧条件下,腈可以直接由醇和代理氨合成。观察到的当前N烷基化反应的催化本质上是非均相的,并且回收的催化剂可以重复使用而不会显着降低催化性能。当前的催化转化将通过连续N次进行烷基化反应,其中醇充当烷基化试剂。根据氘标记实验,建议在N烷基化反应期间形成二氢化钌。
Rapid Multialkylation of Aqueous Ammonia with Alcohols by Heterogeneous Iridium Catalyst under Simple Conditions
titania supports for iridium catalysts strongly affected their activity. The catalysis smoothly proceeded on larger scales. The catalyst could be easily reused and run at least for 5 cycles without significant loss of activity. The highly-dispersed iridium species of less than 2 nm in diameter would be responsible for the excellent catalyticactivity. This catalyst is well applicable in multialkylation of
Process for reductively aminating ketones and aldehydes with aqueous amines and catalysts suitable therefor
申请人:Schramm Daniel
公开号:US20070078282A1
公开(公告)日:2007-04-05
A process for preparing amines of the general formula (I)
R
1
R
2
CHNR
3
R
4
(I)
in which R
1
, R
2
, R
3
and R
4
are each independently hydrogen, straight-chain or branched, halogenated or halogen-free C
1
-C
12
-alkyl, C
3
-C
12
-cycloalkyl, C
6
-C
10
-aryl or C
7
-C
11
-aralkyl, by catalytic, hydrogenating amination of carbonyl compounds of the general formula (II)
R
1
—C(═O)—R
2
(II)
with nitrogen compounds of the general formula (III)
HNR
3
R
4
(III)
in the presence of bifunctional catalyst systems comprising a.) a hydrogenation-active catalyst component comprising one or more metals of transition group 8 of the Periodic Table and b.) one or more solid, acidic cocatalysts, wherein the hydrogenating amination is carried out in the presence of aqueous ammonia or aqueous amine of the formula (III) and at least one organic solvent miscible with ammonia or the aqueous amine of the formula (III).