2,2 -Binaphthalene

Various chiral crown ethers based on [1,1 -binaphthalene]-2.2 -diol, lactose or other chiral 1,2-di-ols were tested as catalyst in the addition of methyl benzcneacetate to methyl 2-propenoate using sodium amide or potassium tert-butoxide as the base. Some pertinent examples are given261 262 396. 

In general the chiral additive (l/ ,2/J)-l,2-dimethoxy-l,2-diphenylethane was the most effective while (.S )-2.2 -diniethoxy-1,1 -binaphthalene and (1 / ,27 )-/V,/V,/V, A"-tetramethyl-1,2-diphcnyl-ethylenediamine induced only very low levels of enantiofacial differentiation. In the case of the acyclic enimines competing 1,2-addition products were also obtained7. 

Tetrahydro-l,l -binaphthalene (bisdialine) (85) is more reactive than the corresponding 1,1 -binaphthalene and has been used as a 47t component of cycloadditions to prepare very complex molecules. An improved method for preparing 85 was recently described [90]. The Diels Alder reactions of 85 with a number of dienophiles were studied [90, 91] and are illustrated in Scheme 2.38. 

The preparation of BINAP reported in 1980 has marked a landmark in asymmetric catalysis and has illustrated the peculiar stereorecognitive properties inherent with the axially chiral 1,1 -binaphthalene framework. Since then, a great deal of work has been devoted to the preparation of binaphthalene-templated ligands of related design. These efforts have resulted in the... 

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

A chiral zirconium catalyst generated from Zr(0,-Bu)4 and (R)-3,3 -diiodo-1,1 -binaphthalene-2,2 -diol [(f )-3,3/-l2BINOL] catalyzed... 

BINAP = 2,2-bis(triphenylphosphino)-1,1-binaphthalene XANTPHOS = 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene... 

R)-(-)-Methyl 3-hydroxybutanoate Butyric acid, 3-hydroxy-, methyl ester, D-(-)-(8) Butanoic acid, 3-hydroxy- methyl ester, (R)- (9) (3976-69-0) [(R)-2,2 -Bls(dlphenylphosphino)-1,1 -binaphthyl]dichlororuthenium Ruthenium, [[1,1 -binaphthalene]-2,2 -diylbis(diphenylphosphine)-P,P ]dichloro- (12) (115245-70-0)... 

The applicability of axially chiral 1, l -binaphthalcnc-8,8 -diol in asymmetric Diels-Al-der reactions was studied by Fuji and colleagues190. They studied the Lewis acid catalyzed reaction of the unsymmetrically substituted maleate ester of 1,1 -binaphthalene-8,8 diol 302 with cyclopentadiene. The diastereoselectivity proved to depend strongly on the Lewis... 

Figure 6.1 exo-2-(S)-Phenylammoniumnorbornan-(R)-1,1 -binaphthalene-2,2 -diyl hydrogen phosphate (2) and its solid-state structure (reproduced with permission from ACS) for determination of the absolute stereochemistry of the chiral product 1. 

Example of a separation using (+)-(PTrMA) [1,1 -binaphthalene]- 2,2 -diol... 

Ruthenium chloride-(S)-BINAP-triethylamine Ruthenium, bis[(1,1 -binaphthalene]-2,2 -diylbis[diphenylphosphineJ-P,P ]di-n-chlorodichloro(N,N-diethylethanamine)di-(12) (114717-51-0)... 

---