Erythrono-1,4-lactone synthesis

In turn, vinylacetic acid served17 for the synthesis of DL-erythrono-1,4-lactone (12). The starting compound was first hydroxylated by means of the barium chlorate-osmium tetraoxide reagent to 3-hydroxybutanolactone, dehydration of which with phosphorus pen-taoxide yielded isocrotonolactone, readily convertible with silver chlorate into 12. 

See Chapter 16 for the synthesis of 2-C-methyl-D-erythrono-1,4-lactone and 2-C-methyl-L-threono-1,4-lactone by asymmetric aldol reaction. 

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