Asymmetric Reaction of α‑Diazomethylphosphonates with α‑Ketoesters To Access Optically Active α‑Diazo-β-hydroxyphosphonate Derivatives

The
first example for asymmetric reaction of diazomethylphosphonates
with α-ketoesters was realized in the catalysis of hydroquinidine-derived
bifunctional thiourea. A methodology was established to access a series
of chiral α-diazo-β-hydroxyphosphonate derivatives containing
various functional groups with high enantioselectivities and yields.
The resulting products could be further transformed into chiral tertiary
β-hydroxyphosphonate and α-halogenated fosfomycin derivatives,
especially α-fluoride analogues.