Suzuki tandem

A portion of the side chain of calyculin was prepared by a tandem reaction sequence that combined an alkenylzinc reagent with 2-bromoethenylboronate, followed by Suzuki coupling with a vinyl iodide in the same pot.230... 

Martin effected the synthesis of several 3,5-diarylated indoles by a tandem Stille-Suzuki sequence [131]. The latter reaction involves exposure of 3-(3-pyridyl)-5-bromo-l-(4-toluenesulfonyl)indole with arylboronic acids (aryl = 3-thienyl, 2-furyl, phenyl) under typical conditions to give the expected products in 86-98% yield [131], Carrera engaged 6- and 7-bromoindole in Pd-catalyzed couplings with 4-fluoro- and 4-methoxyphenylboronic acids to prepare 6- and 7-(4-fluorophenyl)indole (90% and 74% yield) and 6-(4-methoxyphenyl)indole (73% yield) [29]. Banwell and co-workers employed 7-bromoindole in a Suzuki coupling with 3,4-dioxygenated phenylboronic acids en route to the synthesis of Amaryllidaceae alkaloids [132], Yields of 7-arylated indoles are 93-99%. Moody successfully coupled 4-bromoindole... 

Seno H, Hattori H, Ishii A, Kumazawa T, Watanabe-Suzuki K, et al. 2000. Analyses of butyrophenones and their analogues in whole blood by high-performance liquid chromatography-electrospray tandem mass spectrometry. J Chromatogr B Biomed Sci Appl 746(1) 3-9. 

Ohara K, Suzuki Y, Ochiai M, Tsukamoto T, Tani K (1999) A variable-number-tandem-repeat of the serotonin transporter gene and anxiety disorders. Prog Neuropsychopharmacol... 

H Oka, Y Ikai, Y Ito, J Hayakawa, K Harada, M Suzuki, H Odani, K Maeda. Improvement of chemical analysis of antibiotics. 23. Identification of residual tetracyclines in bovine tissues by electrospray high-performance liquid chromatography tandem mass spectrometry. J Chromatogr B 693 337-344, 1997. 

Fig. 16.24. Suzuki coupling for the synthesis of aromatic compounds with a functionalized side chain and regioselec-tive tandem coupling II.

Powell, Maki, and Fu reported a Ni-catalyzed tandem radical 5-exo cyclization/ Stille coupling reaction (Fig. 19) [75]. When allylic bromo ethers 80 were subjected to a reaction with trichlorophenylstannane 81a in the presence of 10 mol% NiCl2 and 15 mol% of bipy 26, bicyclic phenyl-substituted products 82 were isolated in 57-67% yield and moderate to excellent endo-diastereoselectivity. Suzuki-Miyaura-type coupling reactions of 80 with arylboronic acids 81b worked similarly in 69-87%... 

Fig. 43 Palladium-catalyzed tandem carbonylation/Suzuki coupling reactions...

Fig. 46 Light-stimulated palladium-catalyzed tandem radical cyclization/carbonylation/ Suzuki-Miyaura coupling reactions...

Methylene)indolinones have also been prepared by a tandem Heck-carbonylation/Suzuki-coupling [165]. Even though this methodology was further developed with Pd(PPh3)4, the combination Pd(OAc)2/SlPr HBF4 showed comparable activity (Scheme 19). 

Fig. 13.20. Suzuki coupling II for the synthesis of functionalized aromatic compounds regioselective tandem coupling II.

The Pd-catalysed Miyaura-Suzuki coupling of aryltrifluoroborates with 4-tosyloxycoumarins in aqueous conditions offers an attractive route to 4-arylcoumarins <06TL1525> and 4-hydroxycoumarins have been converted into a mixture of predominantly thiopyrano[5, 4 3,4]- pyrano[5,6-c]coumarins and [6,5-c]chromones in a one-pot tandem Knoevenagel - HDA sequence with an S-prenylated 1-phenyl-lff-pyrazole-4-carbaldehyde <06TL2265>. The benzopyrano[4,3-c]benzopyranone system can be obtained from 3-aryl-4-methylcoumarins by deprotonation of the methyl function and subsequent elaboration <06TL5909>. 

Facile synthesis of simple 3-arylpyrroles from pyrroline by tandem Suzuki dehydrogenation reaction is depicted in Scheme 229. Thus, treatment of l-benzyl-2,5-dihydro-l//-pyrrol-3-yl trifluoromethanesulfonate 1195 (prepared in 55% yield from l-benzyl-3-pyrrolidinone 1194 by trapping the enolate with a triflating reagent), with boronic acid derivatives leads to the formation of 3-arylpyrroles 1196 in good yields (65-74%) <2000TL3423>. 

When propargyl allyl ethers are subjected to transition metal-catalyzed enyne cyclization reactions, 3-alkylidene-substituted tetrahydrofurans are usually formed. A useful variation of this scheme is the Pd(0)-catalyzed tandem enyne cyclization/Suzuki coupling reaction with various arylboronic acids (Equation 90) <2005JOC1712>. The stereoselectivity of this reaction is explained by invoking a chairlike transition state. 

Suzuki, T, Beuzenberg, V, Mackenzie, L., and Quilliam, M. A. 2004. Discovery of okadaic acid esters in the toxic dinofiagel-late Dinophysis acuta from New Zealand using liquid chromatography/tandem mass spectrometry. Rapi Commun Mass Spectrom 18, 1131-1138. 

Hashimoto T, Shoji T, Mihara T, Oguri H, Tamaki K, Suzuki Kl, Yamada Y. Intraspecific variability of the tandem repeats in Nicotiana putrescine N-methyltransferases. Plant Mol. Biol. 1998 37 25-37. 

Oka, H. Ikai, Y. Kawamura, N. Uno, K. Yamada, M. Harada, K. Uchiyama, M. Asukabe, H. Mori, Y. Suzuki, M. Improvement of chemical analysis of antibiotics. IX. A simple method for residual tetracyclines analysis in honey using a tandem cartridge clean-up system. J. Chromatogr. 1987, 389, 417-426. 

Suzuki coupling has been used in tandem with Stille coupling. The boronic ester analog of (44) has been coupled to provide (46g).49 Similarly, the boronic ester (48) was coupled with (45b) to afford (49), which then was coupled with an analogous diiodo-derivative to give a shape-persistent bis-tpy macrocycle (Scheme 8). 0... 

Queguiner made great use of Suzuki methodology to prepare heterobiaryls for use in carboline synthesis [169]. This chemistry is discussed in Chapter 4. As explored in more detail in Section 3.5, Grigg developed several Pd-catalyzed tandem cyclization-anion capture processes, and these include organoboron anion transfer agents [109, 170, 171], Two examples of this methodology are shown. 

The 2-indolinone system has been found in a large number of pharmaceutically active compounds. This framework could be constructed by a tandem Heck-Suzuki reaction sequence [137]. Intramolecular Heck reaction of 390 afforded a cyclized intermediate that, in situ, reacted with boronic acid 187 to produce 391 in a single pot sequence. The reaction made use of copper thiophene-2-carboxylic acid (CuTC) to generate base-free conditions for the Suzuki reaction. 

Another use of the indolylborate reagent (69) was reported in the total synthesis of ellipticine analogs by the Ishikura group [46]. As illustrated in Scheme 14, vinylbromide 75 and indolylborate 69 underwent a tandem intramolecular Heck-Suzuki reaction to give hexatriene 76 which was then converted to the desired pyrido(4,3-hlcarbazoie 77 using the well-known photocyclization protocol for styrylindole systems. 

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