Ferrocenyl alkanol

Chiral diol 52 [52] and ferrocenyl alkanol 54 [53] also work as asymmetric autocatalysts in the enantioselective addition of dialkylzincs to the corresponding dialdehyde 51 and ferrocene-carbaldehyde 53, respectively (Scheme 9.26). 

Thus, chiral pyrimidyl alkanol, ferrocenyl alkanol and diol are asymmetric autocatalysts, although the enantiopurities of the newly formed products are moderate. 

Scheme 7 Asymmetric autocatalysts of diol and ferrocenyl alkanol H...

Despite the difficulties as described above in finding efficient asymmetric autocatalysis, we had strong passion to keep doing the research. We modified the structure of original pyridyl alkanol by putting the substituent and also found that a certain chiral diol 8 [25] and ferrocenyl alkanol 9 [26] act as asymmetric autocatalysis (Scheme 7). 

Pyridyl alkanol [41], diol [42], and ferrocenyl alcohol [43] were the first asymmetric autocatalysts found by Soai and co-workers in the enantioselective alkylation of pyridine-3-carbaldehyde, dialdehyde, and ferrocenecarbaldehyde, respectively, with dialkylzincs. 

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