Amberlyst A 21 as new and efficient surface catalyst for the cleavage of 2-nitrocycloalkanones

Article abstract of DOI:10.1055/s-1992-26106

Ring cleavage of 2-Nitrocycloalkanones with methanol/Amberlyst A 21 gave methyl ω-nitroalkanoates, O₂NCH₂(CH₂)(n)CO₂Me where n = 3-6, 8-10,13, in high yield. Subsequent Nef reaction gave the corresponding ω-oxo compounds which were isolated, in the case of methyl 7-oxoheptanoate and methyl 8-oxooctanoate only, or reduced directly with sodium borohydride to give ω-hydroxyalkanoates. A new formal synthesis of exaltolide (15-pentadecanolide) is also reported.