Convenient one-pot synthesis of trans-1,2-diaryloxiranes from the direct coupling of benzyl halides

trans-1,2-Diaryloxiranes were conveniently prepared in an one-pot reaction by the direct coupling of benzyl halides in the presence of silver oxide and DMSO under mild conditions.     

Convenient one-pot synthesis of functionalized （E）-2-arylvinyl bromides from （E）-4-（2-bromovinyl）phenyl acetate

A convenient one-pot synthesis of functionalized (E)-2-arylvinyl bromides was achieved by microwave-induced deacetylation and subsequent acylation using dicyclohexyl carbodiimide (DCC) and dimethylamino-pyridine (DMAP) at room temperature from (E)-4-(2-bromovinyl)phenyl acetate.     

Convenient one-pot synthesis of 2,2-bis-(4-hydroxyphenyl)-cyclopentanone

2,2-Bis-(4-hydroxyphenyl)-cyclopentanone (3a) was unexpectedly obtained in 76% yield from a reductive coupling reaction of 4,4'-dihydroxybenzophenone (1a) and cyclobutanone with TiCl4 and Zn. Further optimization showed that catechol as an external ligand and a hydroxy group on benzophenone facilitated the generation of a quinonemethide (intermediate II) that is involved in the pinacol-type rearrangement of intermediate I to give the rearranged product.     

Iron(III) chloride-catalyzed convenient one-pot synthesis of homoallyl benzyl ethers starting from aldehydes

[reaction: see text] Iron(III) chloride-catalyzed effective allylation reactions of acetals with allyltrimethylsilane proceeded smoothly in high to excellent yields. In addition, this method could be applied to the one-pot synthesis of homoallyl benzyl ethers by a combination of dibenzyl acetalization of aldehydes and consecutive allylation of dibenzyl acetals.     

IBX-mediated one-pot synthesis of benzimidazoles from primary alcohols and arylmethyl bromides

A variety of primary alcohols are shown to be converted to the corresponding benzimidazoles in one pot by employing IBX and o-phenylenediamine in DMSO at room temperature. o-Iodobenzoic acid is the end product of IBX, which is employed in 1.0 equiv. Arylmethyl bromides are also shown to be converted likewise to benzimidazoles in moderate yields in one pot, albeit at slightly elevated temperatures.     

Cu(I) mediated one-pot synthesis of azobenzenes from bis-Boc aryl hydrazines and aryl halides

N,N^′-bis-Boc aryl hydrazines underwent Cu(I) catalyzed couplings with aryl halides to provide N,N^′-bis-Boc diaryl hydrazines. The resulting N,N^′-bis-Boc diaryl hydrazines are readily oxidized to the azobenzenes in the presence of Cu(I) and a base. A prolonged heating of the initial coupling reactions directly provides the corresponding azobenzenes in one pot.     

Base-mediated reaction of vinyl bromides with aryl azides: one-pot synthesis of 1,5-disubstituted 1,2,3-triazoles

A one-pot base-mediated reaction of azides and β- or α-vinyl bromides has been reported. The effects of bases and solvents have been investigated in the process. A variety of 1,5-disubstituted triazoles were prepared in low to good yields. Further studies reveal that the corresponding alkynes were produced as intermediates via elimination reaction. Under the same reaction conditions, the reactions of alkyl alkynes with phenyl azide would give 1,5-disubstituted 1,2,3-triazoles.     

A facile one-pot synthesis of alkyl aryl sulfides from aryl bromides

A convenient one-pot synthetic method for the formation of alkyl aryl sulfides from various alkyl halides and lithium aryl thiolates that are prepared in situ by direct halogen-lithium exchange is reported. In particular, the method overcomes many of the problems encountered in previous reports; it is very quick, catalyst-free, and does not involve use of unstable aryl thiols.     

Iodine-catalyzed one-pot three-component synthesis of homoallyl benzyl ethers from aldehydes

Iodine has been found to be an effective catalyst for one-pot synthesis of homoallyl benzyl ethers under mild reaction conditions. Various homoallyl benzyl ethers were synthesized in moderate to high yield by three-component condensation of aldehydes, benzyloxytrimethylsilane, and allyltrimethylsilane in presence of iodine (10 mol %) in dichloromethane at 0 °C.     

Copper(I)-catalyzed synthesis of 1,3-enynes via coupling between vinyl halides and alkynes or domino coupling of vinyl halides

1,3-Enynes were easily prepared from coupling between vinyl halides and alkynes or domino coupling of vinyl halides in the presence of copper iodide. It is noteworthy that the double-bond geometry of the vinyl halides was retained during the reaction. This ligand-free protocol is potentially useful and practical.     

Zeo-click synthesis: Cu-zeolite-catalyzed one-pot two-step synthesis of triazoles from halides and related compounds

Cu^I-zeolites proved to be an efficient heterogeneous catalyst for the one-pot two-step synthesis of triazoles from halides or tosylates, sodium azide, and alkynes. The step and atom economies of this cascade reaction as well as water used as solvent and catalyst recycling make such synthesis a trully green process. With selected substrates, the peculiar roles of Cu^I-zeolites as catalysts were highlighted.     

N-Phenacylpyridinium bromides in the one-pot synthesis of 2,3-dihydrofurans

A one-pot three-component process for the synthesis of highly functionalized 2,3-dihydrofurans from 1,3-dicarbonyl compounds, aromatic aldehydes, and N-phenacylpyridinium bromides has been developed. Benzylidene 1,3-dicarbonyl compounds could be generated in situ from aromatic aldehydes and 1,3-dicarbonyl compounds and then reacted smoothly with N-phenacylpyridinium bromides to produce 2,3-dihydrofurans in moderate to good yields. Piperidine/acetonitrile is the optimal condition for this process. To increase the efficiency of this reaction, this one-pot process was also conducted solvent-free under classical heating conditions and grinding conditions.     

Effective synthesis of benzyl halides triggered by in situ prepared hypervalent halides

An effective approach for the direct benzylhalogenation with in situ generation of hypervalent halides has been developed.A variety of benzyl halides are produced in moderate to excellent yields(up to 99%) with high regioselectivities.UV absorption spectrum is employed to detect the formation of ferr-butyl hypoiodite.     

An efficient synthesis of benzyl bromides from aromatic aldehydes using polymethylhydrosiloxane and (bromodimethyl)sulfonium bromide or N-bromosuccinimide

Polymethylhydrosiloxane (PMHS) in combination with (bromodimethyl)sulfonium bromide or NBS has been utilized for the first time for reductive bromination of aromatic aldehydes at room temperature to afford the corresponding benzyl bromides in excellent yields.     

A convenient one-pot preparation of glycosyl bromides as well as glycosyl acetates from benzyl glycosides using N-bromosuccinimide.

Some conversions of benzyl glycoside using NBS were examined and one-pot preparation of glycosyl acetates and bromides were developed. An efficient O-debenzylation at non-anomeric position was also observed.     

A one-pot synthesis of nitrogen-containing heteroaryl α-keto amides from heteroaryl halides

The S_NAr-type reaction of the piperidine amide of cyanoacetic acid with a series of heteroaryl halides followed by in situ oxidation of the resultant anion with peracetic acid provided a convenient, one-pot protocol for preparative access to heteroaryl α-keto amides. In this procedure, the amide of cyanoacetic acid functions as an Umpolung-type synthon of the α-keto amide moiety.     

Stereoselective synthesis of functionalized vinyl ethers from allyl bromides activated by triethylamine

An efficient coupling reaction of allyl bromides with various alcohols as nucleophiles activated by triethylamine, leading to functionalized vinyl ethers in good yields and with full stereoselectivity.     

One-pot amide synthesis from allyl or benzyl halides and amines by Pd-catalysed carbonylation

Amides can be prepared from allyl or benzyl halides and primary or secondary amines, using Pd(0) catalyst under CO pressure, in a one-pot synthesis. The reaction proceeds through the acyl palladium halide formation which undergoes an acylic nucleophilic substitution from the amine.