A-benzylidene-2-hydroxyaniline

Achiral ytterbium Lewis acid was prepared from ytterbium triflate [Yb(OTf)3], ( )-(+)-l,l -bis(2-naphthol) (BINOL) and DBU (1), and subjected to aza Diels-Alder reactions of achiral imines (A-benzylidene-2-hydroxyanilines) and achiral dienophiles [79]. In this reaction the use of a chiral Lewis acid containing 1,3,5-trimethylpiperidine instead of 1 resulted in a lowering of the enantiomeric excess of adduct. Thus, the phenolic hydrogen of the imine interacts with DBU (1) in transition state, as shown in Figure 3.7, to increase the selectivity. 

A -benzylidene-2-hydroxyaniline (Bha) and its related derivatives (a-f. Figure 47) can be catalytically oxidized by Oj in the presence of the hydroxo-bridged dicobalt complex [Co2L( i-OH)] (Figure 46) H3L =2,6-bis[(2-hydroxy phenyl)imino-methyll-4-methylphenol in DMF at... 

When heated at 100 °C in dimethylformamide, N-(2,3,4,5,6-pentafluoro-benzylidene)-2,-hydroxyaniline is converted into l,2,3,4-tetrafluorodibenz-[ /] [l,4]-oxazepine 166, formed in a quantitative yield (87JFC(36)93) (Scheme 155). 

A -(2-Hydroxy-3-methoxybenzylidene)-2-hydroxyaniline, in D-00541 A -2-Hydroxy- 5-methoxy benzylidene- 2-hydroxyaniline, in D-00543 A -Hydroxy-4-methoxy-A -... 

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