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1.
Reliable N-alkylations of secondary amines have been developed. By using DIAD and TPP (or PS-TPP) a variety of secondary amines can be converted to the corresponding tertiary amines in good to excellent yields with diverse alkylhalides; no formation of quaternary amine salts are observed. These protocols are amenable to combinatorial chemistry libraries, and are also useful for the syntheses of secondary amines by an acid lysis of the cleavable tertiary amino resins. 相似文献
2.
Unsymmetrical secondary and tertiary amines are prepared by the ruthenium catalyzed reaction of alcohols with amines, which provides highly efficient method for synthesis of cyclic amines. 相似文献
3.
[reaction: see text] An expedient solid-phase synthetic approach to secondary and tertiary amines was developed. The protocol employs conversion of resin-bound amino alcohols to the corresponding iodides, followed by iodide displacement with primary or secondary amines or with unprotected amino alcohols. This two-step procedure, affording products in good to excellent yields, is suitable for solid-phase synthesis of polyamines. 相似文献
4.
Secondary or tertiary amines may be prepared from primary alcohols and primary or secondary amines by treating triphenylphosphine with N-bromosuccinimide (NBS) in the presence of the alcohol at low temperature, followed by addition of the amine and heating for about 1 h. The yield of amine is good to fair, decreasing sharply with sterically congested alcohols and starting amines. 相似文献
5.
A simple and facile method for the synthesis of aromatic tertiary amines by amination of fluoroarenes with secondary amines in the presence of n-butyllithium at room temperature was reported. 相似文献
6.
The direct reductive N-benzylation of imines by reaction with benzyl bromide derivatives, in the presence of [RuCl2(p-cymene)]2 catalyst and PhSiH3, is performed under mild conditions without additional base. This reaction proceeds by a tandem imine hydrosilylation/nucleophilic substitution with benzyl bromide derivatives to result the tertiary amines. 相似文献
7.
Selective N-alkylation of amines using nitriles under hydrogenation conditions: facile synthesis of secondary and tertiary amines 总被引:1,自引:0,他引:1
Ikawa T Fujita Y Mizusaki T Betsuin S Takamatsu H Maegawa T Monguchi Y Sajiki H 《Organic & biomolecular chemistry》2012,10(2):293-304
Nitriles were found to be highly effective alkylating reagents for the selective N-alkylation of amines under catalytic hydrogenation conditions. For the aromatic primary amines, the corresponding secondary amines were selectively obtained under Pd/C-catalyzed hydrogenation conditions. Although the use of electron poor aromatic amines or bulky nitriles showed a lower reactivity toward the reductive alkylation, the addition of NH(4)OAc enhanced the reactivity to give secondary aromatic amines in good to excellent yields. Under the same reaction conditions, aromatic nitro compounds instead of the aromatic primary amines could be directly transformed into secondary amines via a domino reaction involving the one-pot hydrogenation of the nitro group and the reductive alkylation of the amines. While aliphatic amines were effectively converted to the corresponding tertiary amines under Pd/C-catalyzed conditions, Rh/C was a highly effective catalyst for the N-monoalkylation of aliphatic primary amines without over-alkylation to the tertiary amines. Furthermore, the combination of the Rh/C-catalyzed N-monoalkylation of the aliphatic primary amines and additional Pd/C-catalyzed alkylation of the resulting secondary aliphatic amines could selectively prepare aliphatic tertiary amines possessing three different alkyl groups. According to the mechanistic studies, it seems reasonable to conclude that nitriles were reduced to aldimines before the nucleophilic attack of the amine during the first step of the reaction. 相似文献
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9.
Chen Hui Li Hua Yu Qiu Cai Hong Xu 《中国化学快报》2007,18(12):1436-1438
Bis-silicon-bridged stilbene derivatives were synthesized in a modified procedure that combined the preparation of bis[2- (silyl)phenyl]acetylene and its intramolecular reductive cyclization in one pot.The results indicated that the one pot approach produced target products in a comparable yield to that of the two-step method reported previously. 相似文献
10.
Chrysanthemic esters analogues diversely substituted on the cyclopropane ring and on the carbon-carbon double bond can be conveniently prepared in one pot from methyl 4-oxobutenoate by delayed addition of two differently substituted phosphorus ylides. 相似文献
11.
M. Haniti S.A. Hamid 《Tetrahedron letters》2007,48(47):8263-8265
Secondary amines have been converted into tertiary amines by reactions with primary alcohols. A catalytic system of [Ru(cymene)Cl2]2 with dppf has been shown to be effective for this transformation for a range of primary alcohols and secondary amines. The methodology has been applied to the one pot synthesis of Piribedil and other piperazine and morpholine-containing products. 相似文献
12.
V. P. Andreev P. S. Sobolev D. O. Zaitsev L. A. Remizova V. A. Tafeenko 《Russian Journal of General Chemistry》2014,84(10):1979-1988
Stability constants of 46 complexes of zinc(II) tetraphenylporphyrin with primary, secondary, and tertiary amines and thermodynamic parameters of their formation (ΔG 0, ΔH 0, ΔS 0) in chloroform at 283–308 K have been analyzed. Probable factors responsible for enhanced stability of the complexes with ligands containing n-octyl groups are discussed. The X-ray diffraction data for the 1: 1 complex of zinc(II) tetraphenylporphyrin with di-n-octylamine are given. 相似文献
13.
E and Z allylic amines have been synthesised by stereo-specific elimination of Ph2PO2? from pure diastereoisomers (3) and (4). 相似文献
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15.
Three-component synthesis of protected secondary and "for the first time" tertiary homoallylic amines is achieved from carbonyl, carbamate, and allyltrimethylsilanes using a Re(2)O(7)-catalyst under mild and open flask conditions. Excellent chemoselectivities and diastereoselectivities were observed. 相似文献
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17.
A one-pot synthesis of unsymmetrical tertiary amines from amides, lactams and urethanes has been developed. The reaction is general for all cases examined with the exception of N-aryl containing examples, which are not accessible by this method. 相似文献
18.
Various secondary amines were obtained selectively from the reaction of nitroarenes with primary alcohols in the presence of ruthenium(II) complexes having phosphine-amine ligands as the catalyst. Secondary amines could be further alkylated with a primary alcohol using the same catalyst, but different conditions. 相似文献
19.
《Tetrahedron letters》1987,28(21):2383-2386
Oxidation of secondary amines with hydrogen peroxide in the presence of selenium dioxide catalyst at room temperature gives nitrones, which are versatile synthetic intermediates, highly efficiently. 相似文献