2,2 -Binaphthalene derivatives

Scheme 2.2 Cu-catalysed 1,4-additions of ZnEt2 and AlMe3 to ( )-3-nonen-2-one with 1,1 -binaphthalene-derived ligands.

Baumgartner, M.T., Tempesti, T.C. and Pierini, A.B. (2003) Steric effects in the synthesis of ortho-substituted 1,1 -binaphthalene derivatives by the SRN1 and the Stille reaction. ARKIVOK, X, 420 133. 

Oxidative removal of hydrogen has been satisfactory more frequently with phenols and their ethers examples are the conversion of 6-methyl-2-naphthol by iron(ni)284 and of 1-naphthol methyl ether by peroxyformic acid285 into the derived 1,1 -binaphthalene derivatives. 

In recent years, axially chiral binaphthalene derivatives have emerged as important ligands and chiraUty inducers in organic synthesis. Oxidative coupling of 2-naphthols represents a well estabhshed method for the preparation of binaphthols. The couplings are usually carried out by treating naphthols with more than an equimolar amount of a metal such as Fe(III), Mn(III),... 

AIMcs to cyclohexadienone with thioether hgands 86-7 AlMes to linear aliphahc enones with binaphthalene-derived hgands 75-8... 

The breakthrough came already in 1996, one year after Curd s prediction, when Yang and coworkers reported the C2-symmetric binaphthalene-derived ketone catalyst 6, with which ee values of up to 87% were achieved. A few months later, Shi and coworkers reported the fructose-derived ketone 7, which is to date still one of the best and most widely employed chiral ketone catalysts for the asymmetric epoxidation of nonactivated alkenes. Routinely, epoxide products with ee values of over 90% may be obtained for trans- and trisubstituted alkenes. Later on, a catalytic version of this oxygen-transfer reaction was developed by increasing the pH value of the buffer. The shortcoming of such fructose-based dioxirane precursors is that they are prone to undergo oxidative decomposition, which curtails their catalytic activity. 

Many other binaphthalene-derived phosphoramidites were used as chiral ligands in copper-catalyzed Michael additions as well. Whereas 2,2 -bis(diphenylphosphino)-l,T-binaphthalene (BINAP) gave unsatisfactory stereoselectivities in Cu(OTf)2-catalyzed 1,4-additions of diethylzinc to enones,226 BINOL oxazoline phosphites obtained by Pfaltz et al. turned out to be remarkably versatile and in some cases complementary to phosphorami-... 

Since Lusinchi s early work, several groups have identified an interest in oxaziridinium/iminium salt chemistry. Aggarwal and Wang produced a cyclic binaphthalene-derived iminium salt, which was shown to be effective in the epoxidation of 1-phenylcyclohexene, giving 71% ee [11]. This catalyst exhibited high substrate dependency, the best ee for other olefins tested being only 45% (Fig. 5.1). 

Bahr. A. Droz, A.S. Puntener, M. Neidlein. U. Anderson. S. Seiler. P. Diederich, F. Molecular recognition of pyran-osides by a family of trimeric. l,l -binaphthalene-derived cyclophane receptors. Helv. Chim. Acta 1998, 81 (11). 1931-1963. 

Scheme 5.55 Binaphthalene-derived chiral Cp—Rh catalyzed enantioselective C—H hond allylation reaction reported hy Cramer.

On the basis of the previous results. Park, Jew, and co-workers [101] developed in 2009 an efficient synthetic methodology for enantiomerically pure a-alkyl-a,3-diaminopropionic acid. They described the asymmetric PTC alkylation of Af(l)-Boc-2-phenyl-2-imidazoline-4-carboxylic acid /cr/-butyl esters (52) with propargyl, allyl, and substituted benzyl bromides under catalysis with the binaphthalene-derived PTC XXV (Scheme 8.19). Alkylated products were obtained in high yields with excellent enantioselectivities and their acidic hydrolysis furnished corresponding optically active a-alkyl-a,(3-diaminopropionic acids. Another example of PTC alkylation of heterocyclic compounds, namely 1-cyanotetrahydro-(3-carbolines using a binaphthyl-modified V-spiro-type catalyst L, was reported by Maruoka and co-workers [103]. 

A similar receptor design based on a 2,2 -binaphthalene derivative (84) shows a red-shift in the UV-vis spectrum on addition of fluoride, consistent with planarizing of the binaphthyl groups and conformational restriction, although for this receptor, only small changes were observed in the fluorescence emission. 

For the sake of completeness, the synthesis of chiral l,l -binaphthalene derivatives as sensitizers for the photochemical dimerization of cyclohexa-1,3-diene by Vondenhof and Mattay should be mentioned. However, only the racemic sensitizers were employed in the photoreactions, and their potential in asymmetric induction was not examined. 

Atropoisomeric binaphthalene-core phosphacyclic derivatives in coordination chemistry and homogeneous catalysis 97CB543. 

Zeijden [112] used chiral M-functionalized cyclopentadiene ligands to prepare a series of transition metal complexes. The zirconium derivative (82 in Scheme 46), as a moderate Lewis acid, catalyzed the Diels-Alder reaction between methacroleine and cyclopentadiene, with 72% de but no measurable enantiomeric excess. Nakagawa [113] reported l,T-(2,2 -bis-acylamino)binaphthalene (83 in Scheme 46) to be effective in the ytterbium-catalyzed asymmetric Diels-Alder reaction between cyclopentadiene and crotonyl-l,3-oxazolidin-2-one. The adduct was obtained with high yield and enantioselectivity (97% yield, endo/exo = 91/9, > 98% ee for the endo adduct). The addition of diisopropylethylamine was necessary to afford high enantioselectivities, since without this additive, the product was essentially... 

In determination of the absolute configuration of a-chiral primary amines, BINOL derivatives were used as chiral derivatizing agent.10 In this procedure, the chiral substrate was derivatized with R and S enantiomers of the 2,-methoxy-l,l -binaphthalene-8-carbaldehyde and the XH spectra of both diastereomers were compared. Comparison of the chemical shift differences of the diastereomers has allowed determination of the absolute configuration of the chiral substrate [5]. 

Mikami and co-workers16-19 have done extensive work for developing catalysts for the asymmetric carbonyl-ene reaction. Excellent enantioselectivites are accessible with the binol-titanium catalyst 17 (Equation (10)) for the condensation of 2-methyl butadiene (R1 = vinyl) and glyoxalates (binol = l,T-binaphthalene-2,2 -diol).16 The products were further manipulated toward the total synthesis of (i )-(-)-ipsdienol. The oxo-titanium species 18 also provides excellent enantioselectivity in the coupling of a-methyl styrene with methyl glyoxalate.17 Reasonable yields and good enantioselectivites are also obtained when the catalyst 19 is formed in situ from titanium isopropoxide and the binol and biphenol derivatives.18... 

Cooper et al. (26) determined the binding constants and the mobility characteristics for three binaphthyl derivatives with a-, / -, and y-CDs. As shown, the transient diastereomeric complexes of the enantiomers of these compounds differ from each other in their mobilities. This effect is most pronounced in the case of l,l -binaphthalene-2,2 -diyl hydrogen phosphate. The change in enantioseparation depending on the y-CD concentration could be explained well for each solute-y-CD pair based on the binding studies. 

Essentially concurrently, the C2-symmetric ketone catalysts 8-10 were reported . In regard to the enantioselectivity, the TADDOL (o ,Q ,Q , Q -tetraaryl-l,3- oxolane-4,5-dimethanol)-derived ketone 10 performs better than the binaphthalene-based ketone 6, but not as well as the fructose-modified ketone 7, whereas 10 is more resistant than 7 in regard to oxidative degradation. ... 

Kano has studied extensively the recognition of anions and zwitterions by both native and derivatized cyclodextrins [ 16]. The native (3-cyclodextrin com-plexation properties were examined with respect to binaphthyl derivatives. For both l,T-binaphthalene-2,2,-dicarboxylic acid and l,T-binaphthalene-2,2 -diol phosphate almost no chiral recognition was observed. The enantiomers of binaphthyl-2,2 -dicarboxylic acid were better distinguished using a per-O-methylated (3-cyclodextrin derivative in place of the native (3-cyclodextrin. 

In the last two decades, chiral receptors containing amidic functions were designed almost exclusively for binding protected amino acids [49-57], oligopeptides [54,58], and lactic [59], tartaric [60,61] or camphoric acid derivatives [62]. Usually, chiral building blocks such as spirobifluorene [49, 60], binaphthalene [51,57],or amino acid chains containing macrocycles [52-56,58] were employed. An interesting receptor was synthesized via connection of the calix[4]arene moiety with an aza-crown derivative [61]. 

Asymmetric oxidative coupling polymerization of hydroxynaphthalene derivatives was investigated by Habaue and Okamoto et al. First, they studied the oxidative coupling polymerization of optically active 3,3/-hydroxy-2,2/-dimethoxy-1,1 -binaphthalene with copper catalysts bearing chiral ligands under an oxygen atmosphere (Scheme 41) [166]. The obtained polymers had molecular weights of 3100-5200. When the polymerization of (J )-monomer... 

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