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201.
Akbar Heydari Samad Khaksar Maryam Esfandyari Mahmoud Tajbakhsh 《Tetrahedron letters》2007,48(7):1135-1138
A simple and convenient procedure for direct reductive amination of aldehydes and ketones with sodium borohydride is described. The reaction has been carried out in methanol in the presence of a catalytic amount of H3PW12O40 (0.5 mol %). α,β-Unsaturated aldehydes and ketones can be easily converted into the corresponding allyl alcohols by reaction with H3PW12O40 (0.5 mol %)/NaBH4. 相似文献
202.
Hideki Sugimoto 《Tetrahedron letters》2005,46(51):8941-8944
Enantioselective nucleophilic addition of Grignard reagents to N-(2-pyridylsulfonyl)imines in the presence of bis(oxazoline) afforded products with good enantioselectivity. Dynamically induced chirality on the sulfur by coordination of a chiral Lewis acid to a pyridyl nitrogen and one of the sulfonyl oxygens fixes the conformation of the complex and induces enantioselectivity. Since the 2-pyridylsulfonyl group can be easily removed after the addition reaction, it acts not only as a protecting group but also as an efficient stereocontroller. 相似文献
203.
The reaction of [Pt2Me4(μ-SMe2)2] with ligands Me2NCH2CH2NCHAr (2a, Ar=9-phenantryl; 2b, Ar=9-anthracenyl) carried out in acetone at room temperature produced the corresponding compounds [PtMe2{9-(Me2NCH2CH2NCH)C14H9}] (3) in which the imines act as bidentate [N,N′] ligands. Refluxing toluene solutions of compounds 3 gave cyclometallated [C,N,N′] compounds [PtMe{9-(Me2NCH2CH2NCH)C14H8}] (4) as a mixture of two isomers containing either a five- or a six-membered metallacycles for 3a and as a single isomer containing a six-membered metallacycle for 3b. The reactions of compounds 4 with acetyl chloride and with methyl iodide produced, respectively, compounds [PtCl{9-(Me2NCH2CH2NCH)C14H8}] (5) and [PtMe2I{9-(Me2NCH2CH2NCH)C14H8}] (6). All compounds were characterised by NMR spectroscopies and analytical data. 相似文献
204.
1,2‐Diaza‐3‐silacyclopent‐5‐ene – Synthesis and Reactions The dilithium salt of bis(tert‐butyl‐trimethylsilylmethylen)ketazine ( 1 ) forms an imine‐enamine salt. 1 reacts with halosilanes in a molar ratio of 1:1 to give 1,2‐diaza‐3‐silacyclopent‐5‐enes. Me3SiCH=CCMe3 [N(SiR,R′)‐N=C‐C]HSiMe3 ( 2 ‐ 7 ). ( 2 : R,R′ = Cl; 3 : R = CH3, R′ = Ph; 4 : R = F, R′ = CMe3; 5 : R = F, R′ = Ph; 6 : R = F, R′ = N(SiMe3)2; 7 : R = F, R′ = N(CMe3)SiMe3). In the reaction of 1 with tetrafluorosilane the spirocyclus 8 is isolated. The five‐membered ring compounds 2 ‐ 7 and compound 9 substituted on the silicon‐fluoro‐ and (tert‐butyltrimethylsilyl) are acid at the C(4)‐atom and therefore can be lithiated. Experiments to prepare lithium salts of 4 with MeLi, n‐BuLi and PhLi gave LiF and the substitution‐products 10 ‐ 12 . 9 forms a lithium salt which reacts with ClSiMe3 to give LiCl and the SiMe3 ring system ( 13 ) substituted at the C(4)‐atom. The ring compounds 3 ‐ 7 and 10 ‐ 12 form isomers, the formation is discussed. Results of the crystal structure and analyses of 8 , 10 , 12 , and 13 are presented. 相似文献
205.
Pilar Pérez-Puente Juan C. Flores Pilar Gómez-Sal 《Journal of organometallic chemistry》2008,693(26):3902-3906
2-(N-aryliminomethyl)pyrrole precursors (2,6-R2-C6H3-NCH-2-C4H3NH) (R = Me, IH; R = iPr, IIH) were prepared and transformed into their corresponding sodium salts (Na+I− and Na+II−) by treatment with NaH. Both salts readily react with [NiBr2(DME)] (DME = 1,2-dimethoxyethane) to give the respective bis{2-(N-arylimino-κN-methyl)pyrrolide-κN}nickel(II) complexes (1, 2) in almost quantitative yields. The oxidative addition of IH to [Ni(COD)2] (COD = 1,5-cyclooctadiene) results in the formation of 3, which is a mono(iminomethylpyrrolide)-η3-(cyclic-allyl)-type organonickel(II) complex. The crystal structure of compound 1 has been established by X-ray diffraction studies. 相似文献
206.
A convenient one-pot synthesis of ferrocenyl-substituted quinolines via a molecular iodine-catalyzed reaction of ferrocenylimines with enolizable aldehydes is reported. First, nucleophilic addition of the in situ generated enol to ferrocenylimine produces β-anilinopropionaldehyde, which then undergoes intramolecular Friedel-Crafts reaction to give dihydroquinoline derivative. Finally, subsequent dehydration and aerobic oxidation affords ferrocenyl quinolines. 相似文献
207.
Tim G. Elford 《Tetrahedron letters》2008,49(49):6995-6998
α-exo-Methylene-γ-lactams are key structural units in a wide variety of biologically active natural products. A concise route to the formation of polysubstituted α-exo-methylene-γ-lactams is described. In this three-component reaction, an imine is formed from an aldehyde and ammonia in situ, and is subsequently allylated through the use of a 2-alkoxycarbonyl allylboronate. Due to the ester functionality, the addition intermediate subsequently undergoes in situ cyclization to form the observed α-exo-methylene-γ-lactam products. This route allows access to highly substituted α-exo-methylene-γ-lactams in moderate to excellent yields. 相似文献
208.
209.
210.
Yu-Mei Zhang Peng Liu Hong-Li Zhang Zhi-Ming Zhou 《Journal of chemical crystallography》2008,38(2):147-150
Abstract The title compound, (S, R
Fc
)-N-1-(2-diphenylphosphino)ferrocenylethyl-2-hydroxyl-3,5-di-tert-butylbenzalimine was synthesized by the treatment of (S, R
Fc
)-1-(2-diphenylphosphino)ferrocenylamine with 3,5-di-tert-butyl salicylaldehyde and its crystal structure determined. Single crystal X-ray diffraction analysis reveals that the molecular
structure of the title compound is enantiomerically pure. The crystal belongs to noncentrosymmetric, space group P212121, with unit cell parameters a = 9.3792(8) ?, b = 12.6524(10) ?, c = 28.858(2) ?, V = 3424.6(5) ?3, D
x
= 1.221 g cm−3, Z = 4, T = 293(2) K, F(000) = 1336, R
1 = 0.0435 and wR
2 = 0.1039.
Index Abstract The title compound, (S, R
Fc
)-N-1-(2-diphenylphosphino)ferrocenylethyl-2-hydroxyl-3,5-di-tert-butylbenzalimine was synthesized by the treatment of (S, R
Fc
)-1-(2-diphenylphosphino)ferrocenylamine with 3,5-di-tert-butyl salicylaldehyde and its crystal structure determined. Single crystal X-ray diffraction analysis reveals that the molecular
structure of the title compound is enantiomerically pure.
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