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Imines cross-coupling with

The thiazolium-catalyzed addition of an aldehyde-derived acyl anion with a Michael acceptor (Stetter reaction) is a well-known synthetic tool leading to the synthesis of highly funtionalized products. Recent developments in this area include the thiazolylalanine-derived catalyst 191 for asymmetric intramolecular Stetter reaction of a,P-unsaturated esters <05CC195>. However, these cyclizations proceed only in moderate enantioselectivities and yields even under optimized conditions. Thiazolium salt 191 has been used successfully for enantioselective intermolecular aldehyde-imine cross coupling reactions <05JA1654>. Treatment of tosylamides 194 with aryl aldehydes in the presence of 15 mol% of 191 and 2... [Pg.261]

The silyl transfer to imines delivers silaaziridines that can enter cross-coupling with alkynes to afford alylic amines. ... [Pg.415]

Arylation of a wide range of NH/OH/SH substrates by oxidative cross-coupling with boronic acids in the presence of catalytic cupric acetate and either triethyl-amine or pyridine at room temperature in air. The reaction works for amides, amines, anilines, azides, hydantoins, hydrazines, imides, imines, nitroso, pyrazi-nones, pyridones, purines, pyrimidines, sulfonamides, sulfinates, sulfoximines, ureas, alcohols, phenols, and thiols. It is also the mildest method for NIO-vinylation. The boronic acids can be replaced with siloxanes or starmanes. The mild condition of this reaction is an advantage over Buchwald-Hartwig s Pd-catalyzed cross-coupling. The Chan-Lam C-X bond cross-coupling reaction is complementary to Suzuki-Miyaura s C-C bond cross-coupling reaction. [Pg.102]

A useful method for the preparation of functionalised thiazoles has been described. Palladium catalysed cross coupling reactions between 4-thiazolyl-5-acetyl triflates 36 and alkynes afforded 4-alkynyl-5-acetylthiazoles 37 in good yields (56-82%). If 37 is then treated with ammonia in methanol, thiazolo[5,4-c]pyridines 39 are formed, probably via the intermediate imine 38 which then undergos a regioselective 6-endo dig cyclisation <99EJOC3117>. [Pg.193]

Unsymmetrical 1,2-diarylethane diamines, the formal cross-coupling products of two different imines, are produced by intramolecular reactions of dibenzylidene sulfamides with a combination of zinc and Me3SiCl in DME or Sml2 in THF (Equation (57)). [Pg.64]

Unsymmetrical vicinal diamines are prepared by reductive cross-coupling between nitrones and jY-/-butylsulfmyl imines with Sml2. The coupling proceeds in a high diastereoselective manner. Thus, optically pure unsymmetrical vicinal diamines are produced by using enantiomerically pure sulfinyl imines (Equation (74)). ... [Pg.68]

It is known that electrochemical reduction of oximes in protic media occurs in two steps the N—O bond is first reduced to form an imine and the latter is then reduced to afford a primary amine1,29. Tallec has shown that the amine from oxime 33 can be trapped intramolecularly (equation 16)35. Interestingly, the SS diastereomer predominates the chiral pyrrolidine ring derivative serves to control the stereochemistry of formation of the new benzylic chiral center. Electrochemical reductive cross-coupling of O-methyl oximes with carbonyl compounds in isopropanol at a tin cathode affords adducts (equation 17) which can be reduced further to 2-amino alcohols36. In this fashion, menthone could... [Pg.619]

Cross-coupling reactions 5-alkenylboron boron compounds, 9, 208 with alkenylpalladium(II) complexes, 8, 280 5-alkylboron boron, 9, 206 in alkyne C-H activations, 10, 157 5-alkynylboron compounds, 9, 212 5-allylboron compounds, 9, 212 allystannanes, 3, 840 for aryl and alkenyl ethers via copper catalysts, 10, 650 via palladium catalysts, 10, 654 5-arylboron boron compounds, 9, 208 with bis(alkoxide)titanium alkyne complexes, 4, 276 carbonyls and imines, 11, 66 in catalytic C-F activation, 1, 737, 1, 748 for C-C bond formation Cadiot-Chodkiewicz reaction, 11, 19 Hiyama reaction, 11, 23 Kumada-Tamao-Corriu reaction, 11, 20 via Migita-Kosugi-Stille reaction, 11, 12 Negishi coupling, 11, 27 overview, 11, 1-37 via Suzuki-Miyaura reaction, 11, 2 terminal alkyne reactions, 11, 15 for C-H activation, 10, 116-117 for C-N bonds via amination, 10, 706 diborons, 9, 167... [Pg.87]

In addition, the cross-coupling of imines with allyl alcohols to generate Man-nich-type reaction products proceeded efficiently under similar conditions in methanol and ionic liquid ([ l- -butyl-3-methlyimidazolium] PFg) [19, 20] (Eq.9). [Pg.326]

Lithiation of compound 560 with s-BuLi-TMEDA in THF at —78 °C following an inverse addition protocol provided the anion 561. It reacts with primary alkyl iodides and triflates, silyl chlorides, diphenyl disulfide, epoxides, aldehydes, ketones, imines, acyl chlorides, isocyanates and sulfonyl fluorides to yield the expected compounds 562 (Scheme 152). The transmetallation of compound 561 with ZnBr2 allowed the palladium-catalyzed cross-coupling reaction with aryl and vinyl bromides837. When the reaction was quenched with 1,2-dibromotetrafluoroethane, the corresponding bromide 562 (X = Br) is obtained838. [Pg.234]

Cross-coupling between allylic alcohol and aldehyde is efficiently catalyzed by RuCl2(PPh3)3 in water to form an aldol-type product 48 [22], This reaction has limitations in the substituents of the aldehydes, and the use of aliphatic aldehydes provides complicated mixtures. Cross-coupling of imines with allylic alcohols under similar conditions generates Mannich-type reaction products 50 as major products, together with aldol-type products 48 [22], The selectivity of the reaction was improved by using methanol as the solvent, whereupon no aldol-type product was observed (Eqs. 12.19 and 12.20). [Pg.320]

N-Arylated 1,3-propanesultams 236 (R =Ar, R = H) are efficiently prepared from a Pd-catalyzed cross-coupling reaction with different aryl bromides in the presence of Xantphos <2004TL3305>. N-Fluorinated (-l-)-camphorsultams 237 (X = H, Cl, OMe R = F) have been prepared the corresponding imine 16 and difluoro derivative 238 were formed as by-products. The use of 237 is reported in Section 4.05.12.1 <1998JOC9604>. The syntheses of Ar-(l-alkynyl)-Oppolzer s sultams are reported in Section 4.05.6.3.4. Many examples of acylated Oppolzer s sultams are reported in Section 4.05.12.1. [Pg.583]


See other pages where Imines cross-coupling with is mentioned: [Pg.340]    [Pg.1336]    [Pg.77]    [Pg.15]    [Pg.204]    [Pg.148]    [Pg.125]    [Pg.94]    [Pg.344]    [Pg.908]    [Pg.342]    [Pg.352]    [Pg.95]    [Pg.312]    [Pg.175]    [Pg.99]    [Pg.163]    [Pg.320]    [Pg.329]    [Pg.7]    [Pg.68]    [Pg.248]    [Pg.248]    [Pg.288]    [Pg.330]    [Pg.313]    [Pg.48]    [Pg.168]    [Pg.232]    [Pg.248]    [Pg.89]    [Pg.55]    [Pg.95]   
See also in sourсe #XX -- [ Pg.160 ]




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Imines cross-coupling

With imines

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