Helminthosphoral keto aldehydes

Corey and Nozoe cyclized a keto aldehyde as one step in a total synthesis of helminthosphoral (equation 106). In this case, note that the aldehyde enolate adds to the more hindered ketone carbonyl to form a five-membered ring. The alternative addition of the ketone enolate to the aldehyde would give a seven-membered ring. 

---

See also in sourсe #XX -- [ , ]

See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ , ]

See also in sourсe #XX -- [ ]

---