Methyl toluate complex

It may be recalled that an opposite stereochemical result is obtained by employing the bulky aluminum reagents MAD and MAT. This observation has been explained by invoking out-of-plane complexation of the Lewis acid in a direction which would prevent equatorial attack (Figure 48). The X-ray crystal structure of methyl toluate complexed with a bulky aluminum Lewis acid is fully consistent with tius model7 However, it is worth mentioning that a six-membered transition state, perhaps involving [Me2( ArO)Al] Li, has not been considered as an alternative mechanism. 

Figure 22 Ciystal stiucture of Et2 Al(OAr)/methyl toluate complex...

The methyl o-toluate complex [RuCl2(/i -l,2-MeCgH4C02Me)]2 (1) employed in earlier studies on planar chiral areneruthenium complexes proved to be a suitably labile precursor to the tethered arene complexes. It reacts with the donors mentioned above in a 1 2 mol ratio in dichloromethane at room temperature to give quantitatively the corresponding P-bonded adducts [RuCl2( / -... 

TiCU/MgClj/EB/AlEtj/EA Ethyl benzoate (EB) complexes MgCb- Ethyl anisate (EA) or p-methyl toluate added with cocatalyst. 300 92... 

The Dynamit Nobel-Hercules process995 produces dimethyl terephthalate in a more complex synthesis (Scheme 9.25). To overcome the difficulty in the oxidation of the second methyl group, p-xylene and recycled methyl p-toluate formed after... 

Bidentate base.1 The chiral lithium amide of (S)-l has been used to generate the anion of the ethyl o-toluate 2 and as a chiral complexing agent in reaction of the anion with acetaldehyde to give optically active mellein methyl ether (3) in 53% optical yield. Optical yields are markedly lower when a chiral base similar to 1 but lacking the OCH3 group is used. 

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