Photochemical cyclisation of β-allyloxy-carbonyl compounds: synthesis of 2-alkenyl-3-hydroxytetrahydrofurans

Abstract

The /%allyloxy-ketones (1) and (6) undergo cyclisation on U.V. irradiation to yield the 2-alkenyl-3-R3 R' hydroxytetrahydrofurans cyclisation of the aldehyde (2), (12) (3), and has (7)-(10) been used ; similar in a

Cobalt‐Catalyzed Chemoselective Isomerization of 2‐Substituted Allyl Ethers Induced by Hydrogen Atom Transfer

“…Other common solvents such as ethyl acetate, ethanol and acetonitrile were investigated but only 32-41% yields of 2 a were achieved (Table 1, entry 8-10). When (Me 2 SiH) 2 O in entry 1 was replaced with PhSiH 3 or Et 3 SiH, 2 a were obtained in 76% or less than 5% yields respectively (Table 1, entry [11][12]. Trace amounts of product 2 a along with 52% yield of Drago-Mukaiyama hydration product (see supporting information, s1) were generated by employing the reaction under the atmosphere of air (Table 1, entry 13).…”

“…However, the harsh reaction conditions and narrow substrate scopes limit the further application of these methods. Transition metal (Ir, [9] Ru, [10] Pd, [11] Fe, [12] Ni, [13] etc.) catalyzed allyl isomerization has provided an alternative approach for vinyl ether synthesis.…”