Suzuki using

Kuroda and Suzuki used reaction of 267a with 2-bromoaniline leading to anilide 312 as the first step of their sequence in the preparation of 1H-imidazo[4,5-c]quinolin-4(5//)-ones (Scheme 77) (91TL6915). Reaction of 267a with amines usually does not require any catalyst and/or base, but in this case use of sodium hydride was reported. The anilide 312 was sequentially alkylated, first with methyl iodide in ethanol with potassium hydroxide at room temperature and then with different alkyl iodides in acetone at reflux to provide intermediate 313. This compound was then cyclized via palladium catalyzed reaction leading to product 314. This reaction provides a new entry to l//-imidazo[4,5-c]quinolin-4(5//)-ones that are of current interest as antiasthmatic agents. 

Table 5 suggests that one might hope to determine all the constants in the most general anharmonic force field without too much difficulty. The comparison of Suzuki s with Chedin and Cihla s results in Table 6 gives some feel for the reliability of the results obtained. These two calculations were made in different ways (see the original references) although both refined the force field to fit all observed vibrational levels and rotational constants, Suzuki used an up-to-quartic force field, where Chedin and Cihla used an up-to-sextic force... 

One drawback of the Stille coupling is that the tin by-products are toxic and are not easily removed from the product. A solution to this problem developed by Suzuki uses a boronic acid in place of the organ-otin compound. The boron-containing by-products are innocuous and are easily removed because of their solubility in water. The Suzuki coupling has found widespread use in organic synthesis (Scheme 10.20). These reactions are extremely important and the methodology is extensively used, particularly in the search for new pharmaceutical products. 

Vinylation can also be done by Pd-catalysed cross-coupling in which one component is used as a halide or triflate and the other as a stannane (Stille reaction) or boronic acid (Suzuki reaction). Entry 9, Table 11.3, is an example of the use of a vinylstannane with a haloindole. lndole-3-boronic acids, which can be prepared by mcrcuration/boration, undergo coupling with vinyl triflates (Entry 10). 

The Suzuki coupling of arylboronic acids and aryl halides has proven to be a useful method for preparing C-aryl indoles. The indole can be used either as the halide component or as the boronic acid. 6-Bromo and 7-bromoindolc were coupled with arylboronic acids using Pd(PPh3)4[5]. No protection of the indole NH was necessary. 4-Thallated indoles couple with aryl and vinyl boronic acides in the presence of Pd(OAc)j[6]. Stille coupling between an aryl stannane and a haloindole is another option (Entry 5, Table 14.3). 

Ecample Suzuki et. al. used a reaction strategy to expand the Cgo molecule, buckminsterfullerene, by adding divalent carbon equivalents. Adding phenyl diazomethane to Cgo. (I)> followed by the loss of molecular nitrogen, results in a Cgi compound. 

Numerical values for solid diffusivities D,j in adsorbents are sparse and disperse. Moreover, they may be strongly dependent on the adsorbed phase concentration of solute. Hence, locally conducted experiments and interpretation must be used to a great extent. Summaries of available data for surface diffusivities in activated carbon and other adsorbent materials and for micropore diffusivities in zeolites are given in Ruthven, Yang, Suzuki, and Karger and Ruthven (gen. refs.). 

Method of Moments The first step in the analysis of chromatographic systems is often a characterization of the column response to sm l pulse injections of a solute under trace conditions in the Henry s law limit. For such conditions, the statistical moments of the response peak are used to characterize the chromatographic behavior. Such an approach is generally preferable to other descriptions of peak properties which are specific to Gaussian behavior, since the statisfical moments are directly correlated to eqmlibrium and dispersion parameters. Useful references are Schneider and Smith [AJChP J., 14, 762 (1968)], Suzuki and Smith [Chem. Eng. ScL, 26, 221 (1971)], and Carbonell et al. [Chem. Eng. Sci., 9, 115 (1975) 16, 221 (1978)]. 

Under the phase-transfer catalysis conditions, 2-bromo-8-methylquino-line (67) was coupled with 2-pyridylboronic ester 68 to furnish 2-(2-pyridyl)-8-methylquinoline (69) in 56% yield (91JOC6787). At this point, it is opportune to mention that the simple 2-pyridylborane, in contrast to 3- and (4-pyridyl)boranes, is considered an unsuitable Suzuki coupling partner because it forms an unusually stable cyclic dimer resembling a dihydroanthracene. In this case, the obstacle was circumvented by using 2-pyridylboronic ester in place of 2-pyridylborane (Scheme 9). 

In one case, an unpurified sample of pyrrolyl-bisboronic ester 78, synthesized using conditions described by Masuda and coworkers (2000JOC164), was readily engaged in a Suzuki cross-coupling reaction (95JOC7508) with 5-bromoquinoline 77, giving the desilylated product 79 in 29% overall yield (2002JCS(Pl) 1320). 

This method has been applied to a large-scale preparation of 6-bromoindole, which reacts with various arylboronic acids via the Suzuki reaction to afford 6-aryhndoles fEq. 10.50. 6-Bromo-5-methoxyindole for use in the synthesis of marine bromoindole " and 5-amino-7-ethoxycarbonyhndole for use in synthesis of l//-pyrrolo[3,2-g quina2ohne ring system fEq. 10.51 " have been prepared from the appropriate o-nitrotoluene. 

Suzuki, A. Some Aspects of Organic Synthesis Using Organoboranes. 112, 67-115 (1983). 

Palladium-mediated catalysis has only been exploited relatively recently in the synthesis of substituted PPV derivatives. The use of aryl dibromides as monomers is particularly useful as it allows the synthesis of PPVs substituted with alkyl rather than alkoxy sidechains. The Suzuki [53, 54], Heck [55], and Stille [56] reactions have been used in the synthesis of new PPV derivatives, but attaining high molecular weight PPV derivatives by these methodologies has proved problematic. A phenyl-subslilutcd PPV material PPPV 31 was synthesized by a Suzuki coupling (Scheme 1-10) of dibromoethene and fo/.v-boronic acid 30. Its absorption (2ni ix=385 nm) and emission (2max=475 nm) maxima were strongly... 

The authors used a synthesis of 9,9-spirobitluorenes 32 which was developed by Clarksen and Gomberg [60] and which includes the addition of biphenyl-2-yl-magnesium iodide to fluorenone and subsequent cyclization with protic acids. To obtain 2,2,, 7,7 -arylated 9,9-spirobifluorenes 33, 9,9-spirobifluorene (32) was tetrabrominated [58] to yield 34 followed by a Suzuki-type aryl-aryl cross-coupling with various oligoaryl and oligoheteroaryl boronic acids to obtain the 2,2, 7,7 -tetraarylated derivatives 33. 

Using Kishi s modification of the Suzuki coupling procedure,45 Nicolaou et al. accomplished the convergent union of compounds 112 and 113 (see Scheme 28).38b 46 This coupling is the key step in a synthesis of (55,6/ )-dihydroxyeicosatetraenoic acid [(55,6/ )-diHETE] methyl ester (115). Importantly, the configurations of the two coupling partners are reflected in the Suzuki coupling product 114. 

The total synthesis of palytoxin (1) is a landmark scientific achievement. It not only extended the frontiers of target-oriented synthesis in terms of the size and complexity of the molecules, but also led to new discoveries and developments in the areas of synthetic methodology and conformational analysis. Among the most useful synthetic developments to emerge from this synthesis include the refinement of the NiCh/CrC -mediated coupling reaction between iodoolefins and aldehydes, the improvements and modifications of Suzuki s palladium-catalyzed diene synthesis, and the synthesis of A-acyl vinylogous ureas. 

Suzuki, N., et al. (1991). Chemiluminescent detection of active oxygen species, singlet molecular oxygen and superoxide, using Cypridina luciferin analogs. Nippon Suisan Gakkaishi 57 1711-1715. 

Yamaguchi, A., Suzuki, H., Tanoue, K., and Yamazaki, H. (1986). Simple method of aequorin loading into platelets using dimethyl sulfoxide. Thromb. Res. 44 165-174. 

The Suzuki reaction was also used to prepare the polyketone since this particular reaction tolerates the subsequent step (Scheme 6.19).135 Palladium-catalyzed cross-coupling of aromatic diacid chlorides and bis(trimethylstannane) monomers was utilized to prepare poly(arylene ether ketone)s.136... 

At about die same time, die application of the Suzuki coupling, the crosscoupling of boronic acids widi aryl-alkenyl halides in die presence of a base and a catalytic amount of palladium catalyst (Scheme 9.12),16 for step-growth polymerization also appeared. Schliiter et al. reported die synthesis of soluble poly(para-phenylene)s by using the Suzuki coupling condition in 1989 (Scheme 9.13).17 Because aryl-alkenyl boronic acids are readily available and moisture stable, the Suzuki coupling became one of die most commonly used mediods for die synthesis of a variety of polymers.18... 

---