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Arylboronic acid added

The optimal reaction conditions were applied with 59d in the addition of various aryl boronic acids and potassium trifluoroborates to several cyclic and acyclic enones (Fig. 8). Arylboronic acids added to cyclic enones in high yields (89-97%) and with good to excellent selectivities (85-98% ee). Under these conditions, the potassium trifluoroborate reagents reacted at faster rates, but with slightly lower selectivities (83-96% ee). The reactions of acyclic enones with aryl boron reagents gave also excellent yields (83-96%). [Pg.214]

Arylboronic acids added to alkynes975-977 and activated alkenes such as norbornene978-981 or 2-vinylpyridines982 in the presence of a rhodium(i) catalyst. Addition of arylboronic acids to allenes was reported to be catalyzed by Pd(PPh3)4 in the presence of AcOH.983... [Pg.215]

In cross-coupling with arylboronic acids, some Cu1 carboxylates were found to provide a way to realize a very mild, base-free procedure, which is helpful in cases when added base can induce side reactions (59).222... [Pg.326]

Suzuki Coupling to Displace the Remaining Chloro Atom on C2 with Aryl Groups (Fig. 10).15 To a 10-ml flame-dried Schlenk flask containing the solid supported intermediate 61 (0.10 mmol, 1.0 equiv.) are added an arylboronic acid (0.50 mmol, 5.0 equiv.), Pd2(dba)3 (0.007 mmol, 0.07 equiv.), l,3-bis(2,6-diisopropylphenyl)-lH-imidazol-3-ium chloride (carbine ligand, 0.014 mmol, 0.14 equiv.), and Cs2C03 (0.60 mmol,... [Pg.465]

Arylboronic acids have been added diastereo- and enantio-selectively to (a) sulflnyl aldimines and (b) phosphinoyl aldimines, using rhodium(I) catalysts.52 These two methods should prove useful in preparing a-branched amines. [Pg.7]

Biaryl coupling by ligand 18c [33] A flask was charged with Pd(OAc)2 (0.01 mmol), 18c (0.02 mmol), arylboronic acid (1.5 mmol), and KF (3 mmol). The flask was evacuated and backfilled with argon, and THF (1 ml) and chloroarene (1 mmol) were then added. The mixture was stirred at room temperature until the starting chloroarene was completely consumed (2-24 h). The reaction with phenylboronic acid 4-chloroanisole (6 h, 93%), 2-chloroanisole (24 h, 96%), 4-chlorotoluene (6 h, 95%), methyl 4-chlorobenzoate (2 h, 91%), 3-chloropyri-dine (9 h, 94%). [Pg.17]

Biaryl coupling by ligand 21 [36] A Schlenk tube charged with Pd2(dba)3 (0.015 mmol) and 21 (0.03 mmol) and CS2CO3 (2 mmol) was flushed with argon. 1,4-Dioxane (3 ml), chloroarene (1 mmol) and arylboronic acid (1.5 mmol) were added, and the mixture was then stirred for 1.5 - 2 h at 80 °C. [Pg.17]

Careful optimization of the reaction conditions has been undertaken, thus showing the need to pre-form the intermediate iminium ion in dry THE for 2 h before adding the supported boronic acid and the appropriate volume of THE/EtOH 8 3 (v/v). The process is driven by the large excess of ethanol and by the consumption of the boronic ester, which adds to the iminium ion intermediate. Solid-supported acyclic amines were equally successful, while the main limitation of the process stems from the fact that only electron-rich arylboronic acids gave good conversions. [Pg.271]

Instead of aryl halides, arenediazonium salts are also excellent arylating agents in the Suzuki coupling, although more hindered arylboronic acids did not react The reaction is catalysed by several sources of ligand-free palladium such as Pd(OAc)2, Pd2(dba)3 and Pd/C at room temperature in dioxane without any added base [98]. Use of potassium aryl trifluoroborate salts also allowed the introduction of more sterically hindered aryl groups [99]. [Pg.323]

General procedure Ni(cod)2 (5.6 mg, 0.020 mmol), bathophenanthroline (13.2 mg, 0.040 mmol), the arylboronic acid (0.60 mmol), and KO-/-Bu (90 mg, 0.80 mmol) were added to a vial equipped with a stir bar. The vial was evacuated/refilled with Ar three... [Pg.330]

In 2006, the group of Artok showed that 5-aryl-2(5H)-furanones could be prepared in moderate to good yields by a rhodium-catalyzed carbonylative arylation of internal alkynes with aryl boronic acids (Scheme 1.9a) [22]. a,P-Unsaturated ketones (chal-cone derivatives) were formed as the major product when some TFA (trifluoroacetic acid) was added under the same reaction conditions [23a]. By varying the catalytic system, indanones could be produced as the main product [23b]. The chemical behavior of terminal alkynes is different, and either a,P-unsaturated ketones or furans starting from propargylic alcohols can be achieved (Scheme 1.9b) [24, 25]. In the case of vinyl ketones, 1,4-diketones were obtained by rhodium-catalyzed coupling of arylboronic acids in the presence of 20-40 bar of CO [26]. In 2007, Chatani demonstrated that indenones could be accessed by a carbonylative rhodium-catalyzed cyclization of alkynes with 2-bromophenylboronic adds (Scheme 1.9c) [27]. Here, the key intermediate is a vinylrhodium(I) spedes that is formed by transmetaUation of RhCl with 2-bromophenylboronic acid followed by insertion of... [Pg.13]

Due to their widespread application in the Suzuki-Miyaura reaction, arylboronic acids are attractive aryl transfer precursors. However, in the zinc-promoted reaction, an excess of Et2Zn (up to 7equiv.) must be added in order for efficient transmetallation to occur. The application of a reactive aryl metal species necessitating only a catalytic amount of metal would thus be advantageous. In recent years, several rhodium-catalyzed enantioselective protocols have been described, as well as processes involving palladium and nickel. [Pg.274]

A 10 mL round bottom flask was charged with an arylboronic acid (1 1.2 mmol), CuCl (10 mol %) and the corresponding sulfonyl azide (2 1.0 mmol). 2 mL of methanol was then added to the flask. The reaction mixture was stirred (0.5 - 3 h) at room temperature in an open flask. After completion of the reaction, the solvent was removed in vacuo and the residue was purified by flash column chromatography on silica gel to obtain pure N-aryl/heteroaryl sulfonamide 3. All the products were characterized by spectral methods. [Pg.91]

Enantioselective arylation of ketimines has been carried out using rhodium catalysis with chiral sulfur-olefin ligands arylboronic acids are added in up to 99/99% yield/cc. 0... [Pg.14]


See other pages where Arylboronic acid added is mentioned: [Pg.524]    [Pg.243]    [Pg.286]    [Pg.168]    [Pg.243]    [Pg.269]    [Pg.484]    [Pg.337]    [Pg.428]    [Pg.20]    [Pg.57]    [Pg.901]    [Pg.464]    [Pg.514]    [Pg.179]    [Pg.471]    [Pg.243]    [Pg.66]    [Pg.847]    [Pg.322]    [Pg.750]    [Pg.750]    [Pg.172]    [Pg.244]    [Pg.97]    [Pg.148]    [Pg.1486]    [Pg.101]    [Pg.29]    [Pg.76]    [Pg.241]    [Pg.361]    [Pg.409]    [Pg.172]    [Pg.244]   


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Arylboronates

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