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1.
The Pd(II)-catalyzed reaction of arylboronic acids and internal alkynes provides a convenient route to a wide variety of tetrasubstituted olefins. The reaction is conducted in DMSO using molecular O2 as an oxidant in the absence of any base. The reaction involves the cis addition of two aryl groups from the arylboronic acid to opposite ends of the triple bond of the internal alkyne. The synthesis tolerates a wide variety of functional groups, including alcohol, aldehyde, ester, TMS, and acetal groups. Electron-rich dialkylacetylenes, such as 4-octyne, provide highly substituted 1,3-dienes in moderate yields. The very mild O2/DMSO conditions also afford good to excellent yields of biaryls by the homocoupling of arylboronic acids. 相似文献
2.
[reaction: see text] The Pd-catalyzed three-component coupling of readily available aryl iodides, internal alkynes, and arylboronic acids provides a convenient, one-step, regio- and stereoselective route to tetrasubstituted olefins in good to excellent yields, although electron-poor aryl iodides and dialkylalkynes normally afford only low yields under our standard reaction conditions. The proper combination of substrates and reaction conditions is important for high yields. The presence of water generally substantially increases the yields of the desired tetrasubstituted olefins. The reaction involves cis-addition of the aryl group from the aryl iodide to the less hindered or more electron-rich end of the alkyne, while the aryl group from the arylboronic acid adds to the other end. A modified, room-temperature procedure has also been successfully developed, which works very well for some substrates. Tamoxifen and its derivatives are synthesized in a concise, regio- and stereoselective manner by applying our synthetic protocol. 相似文献
3.
Highly effective Pd-catalyzed Heck-type oxidative couplings between arylboronic acids and terminal olefins were reported. It is noteworthy that such reactions could be carried out in the absence of the base and the ligand. 相似文献
4.
The 1:2 coupling of aryl iodides with acetylenedicarboxylate esters and diphenylacetylene efficiently proceeds in the presence of a palladium catalyst with use of silver carbonate as base to produce the corresponding tetrasubstituted naphthalenes. 相似文献
5.
The palladium-catalyzed cross-coupling of chlorotrifluoroethylene and arylboronic acids proceeds in the presence of a base and H(2)O to provide α,β,β-trifluorostyrene derivatives in satisfactory yields. 相似文献
6.
[reaction: see text] Arylboronic acids react with aldehydes in the presence of a base and a catalytic amount of a palladium(0) complex with chloroform, affording the corresponding secondary alcohols in good yields. General palladium complexes have no catalytic activity without chloroform. Chloroform is essential for this reaction, and palladium complex that was prepared from Pd(PPh3)4 with CHCl3 showed good catalytic acitivity as well. 相似文献
7.
The facile addition reaction of boronic acids to oxabenzonorbornadienes was achieved using a catalytic amount of a rhodium(I) complex having P(OEt)3 ligands, affording cis-2-aryl-1,2-dihydro-1-naphthol stereoselectively, and in good yield without concomitant deboronation of the boronic acid. 相似文献
8.
The addition of arylboronic acids to isocyanates catalyzed by palladium acetate in the presence of triphenylphosphine as the ligand is described. 相似文献
9.
Reaction of symmetrical and unsymmetrical alkynes with arylboronic acids, using PdCl2 as catalyst source and i-Pr2NPPh2 as ligand, afforded trisubstituted alkenes with regioselectivity in good to excellent yields without a common additional acetic acid. Its efficiency has been demonstrated by its good functional groups, high yield and crowded substrates. 相似文献
10.
A novel NiH-catalyzed decarboxylative hydroalkylation of internal alkynes has been developed. Trisubstituted olefins were obtained in moderate to good yields with good regioselectivities. The reaction involves cis addition of NiH to the internal alkyne. The reaction shows good functional-group tolerance. 相似文献
11.
In the presence of a rhodium complex containing a newly developed chiral diene ligand, alkenes activated by a range of π-deficient or π-excessive heteroarenes engage in highly enantioselective conjugate additions with various arylboronic acids. 相似文献
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Sabrina M. Nobre 《Tetrahedron letters》2004,45(44):8225-8228
A simple catalyst precursor prepared in situ from palladium acetate and triphenylphosphine shows high activity for the Suzuki cross-coupling reaction of benzylic bromides and chlorides with aryl boronic acids. The reaction can be carried out at low catalyst loading (0.002-1 mol%) and under mild conditions (room temperature to 80 °C) furnishing diarylmethane derivatives in high yields (86-99%). 相似文献
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15.
The addition of arylboronic acids 1 to azodicarboxylates 2 in the presence of a catalytic amount of a copper salt under mild reaction conditions gives aryl-substituted hydrazines 3 in high yields. The reaction is tolerant of a wide variety of functional groups. 相似文献
16.
The CuOAc-catalyzed reaction of internal alkynoates with arylboronic acids proceeded under mild conditions to yield trisubstituted cinnamates stereoselectively. 相似文献
17.
A new procedure has been developed for constructing arylalkynes through cross-coupling of terminal alkynes with arylboronic acids catalyzed by a palladium-silver system under mild conditions. 相似文献
18.
Martina SL Jagt RB de Vries JG Feringa BL Minnaard AJ 《Chemical communications (Cambridge, England)》2006,(39):4093-4095
The catalytic asymmetric 1,2-addition of a series of arylboronic acids to 2,2,2-trifluoroacetophenones is described with high isolated yields (up to 96%) and good enantioselectivities (up to 83% ee) using a rhodium(I)/phosphoramidite catalyst. 相似文献
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[reaction: see text] The first asymmetric palladium-catalyzed conjugate addition of arylboronic acids to alpha,beta-unsaturated aldehydes, ketones, and esters is described. For cyclic substrates, excellent chemo-, regio-, and enantioselectivities are achieved when a Pd(O2CCF3)2/DuPHOS catalyst is applied. 相似文献