Borates, pyrrol

B-C bonds, 3, 97 B-N bonds, 3, 97 B-O bonds, 3,94 B-P bonds, 3, 97 B-Si bonds, 3, 97 oxo acid anion complexes, 3, 96 Borates, alkoxo-, 3, 94 Borates, amidotrihydro-, 3,92 Borates, aryloxo-, 3, 94 Borates, carboxylato-, 3,96 Borates, catechol, 3,95 Borates, chlorosulfato-, 3,97 Borates, dicarboxylato-, 3,96 Borates, dipyrazol-l-yl-, 3, 92 Borates, halogeno-, 3,92 Borates, halogenohydro-, 3,90 Borates, hydro-, 3,90 Borates, hydrohydroxo-, 3,90 Borates, hydropyrazol-l-yl-, 3, 92 Borates, hydroxo-, 3,94 Borates, hydroxycarboxylato-, 3,96 Borates, inositol, 3, 95 Borates, monoalkyl-, 3, 92 Borates, monophosphido-, 3, 92 Borates, peroxohydroxo-, 3, 94 Borates, polyol, 3, 95 Borates, pyrrol-l-yl-, 3, 92 Borates, sulfato-, 3, 97 Borates, tetrabromo-, 3, 92 Borates, tetrachloro-, 3, 92 Borates, tetrafluoro-, 3, 92 minerals, 6, 847 Borates, tetrahalogeno-mixed, 3, 93 nB NMR, 3, 92 Borates, tetraiodo-, 3, 92 Borates, tetranitrato-, 3, 96 Borates, tetraperchlorato-, 3, 97 Borates, tripyrazol-l-yl-, 3, 92 Borax, 3,101 Borazines... 

As we have seen in Chapter 1, the Suzuki coupling reaction is a powerful method for preparing biaryls and several applications in pyrrole chemistry have been described. Schliiter reported the first pyrrole boronic acid 57, but, surprisingly, the related pyrrole borate 58 could not be hydrolyzed [15]. 

The same authors <2000J(P1)3584> studied the reactivity of 2 toward benzenediazonium (chloride or tetrafluoro-borate) salts. No diazo coupling took place under neutral or slightly acidic conditions. However, under basic conditions (NaOH in H20/MeOH), a mixture of 62 and 63 was obtained. This result clearly indicates that the diazo coupling takes place through the anion of 62 which arises from the base-catalyzed methanolysis of amide 2 in which the pyrrole ring is obviously not nucleophilic enough. 

Other azaheterocyclic borates to have been similarly utilized include the 3-quinoline, 4-isoquinoline, l-methyl-2-pyrrole, and 1-methyl 2- and... 

The whole series of pyrrol-l-ylborates, M[BH (NC4H4)4 ], has been synthesized (Tables 9 and 12). The mechanism of their formation and their hydrolysis kinetics have been studied in detail.100 The hydropyrazol-l-ylborates are very stable compounds and can be prepared in acid form.101 The di- and tri-pyrazol-l-ylborates are extensively used as complexing ligands (see Chapter 13.6). The photoelectron spectra of the sodium and thalliumfl) hydrotris(pyrazol-l-yl)borates and the electronic structure of the anion itself are reported.11 ... 

Imines also form adducts with B(C6F5)3, and Erker et al.144 and Resconi and coworkers136 have used this to clever advantage in preparing a new family of Bronsted acids comprised essentially of the B(C6F5)3 adducts of the thermodynamically less stable tautomers of pyrrole and derivatives (Entries 21 and 22, Scheme 20). Erker s preparation of the compound relies on protonation of the lithium pyrrolyl borate with HC1 Resoni has... 

Reactions between metal complexes and organic substrates in the condensed phase usually begin with the eoordination of these reactants. Due to 7t- and n-electrons present in the molecules of substances frequently employed in catalytic processes (such as olefins, acetylenes, carbon monoxide) they are capable of forming rather stable complexes with transition metals. For example, the complex TpRe(CO)2(THF) (Tp = hydridotris(pyrazolvl)borate THF = tetra-hydrofiiran) reacts with a variety of aromatic molecules to form stable binuclear complexes of the form TpRe(CO)2 2(fi-r LTi -L), where L = fiiran, Al-methyl-pyrrole, or naphthalene [3a] ... 

Although Li[B(NHMe)4] exists,most tetraamidoborates contain ligands derived from five-membered heterocyclics such as pyrrole, indole, imidazole, pyrazole and indazole. The thermal and hydrolytic stabilities of these borates are fairly hi. When the heterocycle contains two nitrogens the borates can exist in acidic form and the tetraimidazol-l-ylborate can be used for gravimetric determination of the proton. Another type of borate containing a BN4 unit is represented by bicyclic derivatives formed with iV,iV",iV"-trimethylbiuret. ... 

Py pyrrole, MPy 1-methylpyrrole, PPy polypyrrole, PMPy poly(l-methylpyrrole), EDOT 3,4-ethylenedioxytiophene, PEDOT poly(3,4-ethylenedioxytiophene), MT 3-methylthiophene, PMT poly(3-methylthiopliene), NaPSS sodium polystyrene sulfonate, NaDBS sodium dodecylbenzenesulfonate, NaPTS sodium para-toluene sulfonate, BSA benzenesulfonic acid, SSA 2-hydroxy-5-sulfobenzoic acid, MES 2-(Af-morpholino) ethanesulfonic acid, MOPS 3-(Al-morpholino) propanesulfonic acid, PIPES piperazine-l,4-bis(2-ethanesulfonic) acid, MeCN acetonitrile, DCE 1,2-dichloroetane, BU4NPF6 tetrabutylammonium hexafluor-ophosphate, BTPPA-CIO4 bis(triphenylphosphoranylidene)ammonium perchlorate, BTPPA-TFPB bis(triphenylphosphoranylidene)ammonium tetrakis[3,5-bis (trifluoromethyl)phenyl]borate, TPenA tetraphenylammonium... 

Electrically stimulated release of glutamic acid from a poly(pyrrole) microtip in 0.2 mol dm borate buffer solution (pH 9.0). After Reference [1024], reproduced with permission. 

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