Methyl rocaglate

Porco et al. reported the synthesis of ( ) methyl rocaglate using [3 + 2] dipolar photocycloaddition reaction of an oxidopyrylium betaine derived from excited state intramolecular proton transfer reaction of 3-hydroxyflavin and methyl cinnamate [144]. Methyl rocaglate was obtained by a base-mediated a-ketol rearrangement followed by hydroxy-directed reduction sequence. They subsequently succeeded in the asymmetric synthesis of methyl rocaglate using functionalized TADDOL derivative (34) (Figure 2.30) as a chiral Bronsted acid (Scheme 2.77) [145]. 

Porco and coworkers used taddol 10 as a chiral H-bond donor in the asymmetric photochemical [3-f2] cycloaddition between oxidopyrylium betaine generated from 11 and methyl cinnamate 12 (Scheme 10.11) [72]. (-)-Methyl rocaglate was obtained... 

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