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1.
Cyclotriveratrylene (CTV) can be readily synthesized by chloromethylation or bromomethylation of dimethoxybenzene with halomethyloctyl ether in the presence of SnCl4. The reaction provides the trimer exclusively and in high yield. Recrystallizations from benzene or CHCl3 yielded the solvent inclusion complexes and did not remove other inclusion impurities. Flash chromatography on silica yielded the pure CTV.13C NMR shows only five signals and no impurities.  相似文献   

2.
《Tetrahedron: Asymmetry》2007,18(21):2507-2509
A simple and efficient procedure for the synthesis of N-sulfinylaldimines (sulfinimines) from sulfinamides and aldehydes is described. The reaction was carried out in the presence of t-BuOK or NaOH. The method is applicable for the synthesis of optically active sulfinimines.  相似文献   

3.
The psychoactive isoxazole muscimol 10 has been synthesized in three steps from propargyl chloride.  相似文献   

4.
A facile synthesis of a functionalized cyclononatripyrrole derivative is described. It involves the iodine-catalyzed cyclotrimerization of ethyl 3,3-dimethyl-5,7-dihydro[1,3]dioxepino[5,6-c]pyrrole-6-carboxylate in methanol. The product obtained in this way exists solely in the crown conformation typical of cyclononatripyrroles. However, in contrast to previously reported compounds of this class, it possesses three labile methoxymethyl arms that can be further functionalized under acidic conditions.  相似文献   

5.
A one-pot synthesis of 1, 3 and 4-cyanophenothiazines and a two-step approach to 2-cyanoisomer have been developed. The condensation of 2-aminobenzenethiol and 2,3 or 3,4-dihalogenobenzonitriles followed by Smiles rearrangement or by intramolecular aromatic substitution gave the desired ring systmes.  相似文献   

6.
7.
《Tetrahedron letters》1987,28(20):2251-2254
Ulicyclamide (1), a cytotoxic cyclic peptide from a marine tunicate, has been efficiently synthesized by the solid-phase method using diethyl phosphorocyanidate for the coupling and trimethylsilyl triflate for the final deprotection.  相似文献   

8.
2(-Benzoxazolyl substituted cyclopropane derivatives were synthesized in the yield of 73-89% from the reaction of telluronium ylides with chalcones.  相似文献   

9.
Dieter RK  Yu H 《Organic letters》2000,2(15):2283-2286
alpha-Aminoalkylcuprates prepared from CuX.2LiCl (X = Cl, CN) and 1 equiv of an alpha-lithiocarbamate undergo conjugate addition reactions to alpha,beta-alkynyl ketones in moderate to good yields, affording E:Z mixtures of alpha,beta-enones. Treatment of the conjugate adducts with PhOH/TMSCl in CH(2)Cl(2) effected carbamate deprotection and cyclization to afford a flexible two-step synthesis of substituted pyrroles.  相似文献   

10.
林国强  柳谨  丁维钰 《化学学报》1991,49(11):1142-1144
六碳醛糖与1,3-双桐或β-酮酸酯在氯化锌存在下缩合, 再经酸性条件下环化生成50-60%得率的5-四氢呋喃基呋喃类化合物。  相似文献   

11.
A one-step synthesis of ( )-deoxypseudophrynaminol, a racemic deoxy analog of the natural product pseudophrynaminol, is described.  相似文献   

12.
Asterriquinone D was easily synthesized in three steps from 2,5‐dichloro‐1,4‐benzoquinone. The reaction of benzoquinone with indole in the presence of Pd(OAc)2, followed by oxidation with cerium (IV) ammonium nitrate (CAN) produced 3,6‐dichloro‐2,5‐bis (3‐indolyl)‐1,4‐benzoquinone. The methoxylation of the dichloride with NaOH in CH3OH afforded asterriquinone D.  相似文献   

13.
A short and convergent approach for the synthesis of shikalkin (dl-shikonin) is presented. Stobbe reaction was employed to construct the aromatic skeleton 6. This is followed by a practical method to prepare the key epoxides 9 from aldehydes 8 in high yield. Finally, shikalkin is achieved by Grignard reaction and oxidation.  相似文献   

14.
2,3-Azaisoindoline (4) was prepared via reaction of dichloride 11 with 2,4-dimethoxybenzyl amine followed by deprotection with trifluoroacetic acid and triethylsilane. Isolation of the unstable 2,3-azaisoindoline 4 was facilitated by conversion to the bis-HCl salt.  相似文献   

15.
A facile and versatile method for the synthesis of unsymmetrical ureas from readily available reagents is reported. In the first step trifluoroethylchloroformate is reacted with a stoichiometric amount of a primary amine to give an intermediate trifluoroethyl carbamate. The addition of a second amine (primary or secondary) to the trifluoroethyl carbamate furnishes corresponding unsymmetrical ureas in 75-85% yield. A simple workup procedure, the high yields obtained, and the purity of the isolated products are suitable for the parallel synthesis of combinatorial libraries of unsymmetrical ureas with high structural and functional diversity.  相似文献   

16.
17.
Fluorochlorobromoacetic acid was sythesized in the sequence of four steps from 1,1,2-trifluoro-2-chloroethylene in an overall yield of approximately 25%. 1,1,2-Trifluoro-2-chloroethylene was first allowed to react with sodium methoxide to form 1,2-difluoro-1-chloro-2-methoxyethylene, which was then brominated with elemental bromine and the reaction product treated with concentrated sulfuric acid to give methyl fluorochlorobromoacetate. This compound was hydrolized with a diluted sodium hydroxide solution to fluorochlorobromoacetic acid.This paper is dedicated to Professor Karl Schlögl on the occasion of his 65th birthday with warmest personal wishes  相似文献   

18.
19.
The indoloquinazoline alkaloid rutaecarpine has been synthesized efficiently by employing 9,10,11,12-tetrahydro-4H-pyrido[2,1-b]quinazoline-4,9-dione (4) as a key intermediate, which was prepared by adapting a Dieckmann condensation-decarboxylation sequence from quinazolinone diester 6.  相似文献   

20.
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