Total Syntheses of Patulin

The initial synthesis of Woodward and Singh was reported for patulin (348) in 1950 (297). However, the yield was low and the synthesis impractical. Two almost identical syntheses were reported independently by the groups of Stapleton in 1988 298, 299) and Riguera in 1989 300). Both commenced from L-arabinose, a readily available starting material from the chiral pool notwithstanding this, deprotection of a late-stage acetal intermediate to deliver the natural product was followed, perhaps unsurprisingly, by rapid racemization at the hemiacetal center. For details of these earlier syntheses, the reader is directed to our recent review (70) and the primary literature. 

Rychlik and Schieberle reported a synthesis of C-labeled patulin (348) in 1998 (303). The synthesis was from L-arabinose (363), as described by Stapleton and coworkers (298), with an initial methyl acetal formation, protection of a 1,2-diol, then 

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