The development of the chemistry of furans, 1952-1963

Synthesis of 3‐Substituted Furans by Hydroformylation

“…It is interesting to note that alkylpropargylic alcohols did not give the expected cyclic products when the phenyl group was substituted with an alkyl group such as C 2 H 5 , Me(CH 2 ) 5 or Me(CH 2 ) 6 .…”

“…[1] Synthetic access to these compounds is not straightforward, due to difficulties encountered in the preparation of 3-furyl synthons. [6] In 1971, Botteghi et al [7] reported that 3-substituted furans can be synthesized through the hydroformylation of allylic alcohols. This is the first method used for the synthesis of 3-substituted furans using hydroformylation reaction conditions.…”

Synthetic Studies in the Veratrum Alkaloid Series. II. The Total Synthesis of Verarine, Veratramine, Jervine, and Veratrobasine

“…Documented data indicate that only furans with electron-withdrawing substituents (e.g., -COOR group) at C, can direct substitution to C, whereas the presence of electron-donating substituents invariably direct the substitution to C, (20). A more detailed investigation is now reported from our laboratory (24).…”

“…The 0.r.d. curves of 3-keto steroids with the 5a and 5P configuration have been extensively studied and Masamune et al The hydrogenation products which had tentatively been assigned the 5a (11) and 5P (20) configurations were converted to the respective 3-keto compounds (23 and 24) using Jones' reagent as the oxidizing agent. The presence of the Nacetyl group tended to complicate the 0.r.d.…”

“…In fact only limited data on the electrophilic substitution of 3-alkylfurans in general was available and the data indicated that the substitution takes place exclusively at the 2-position (19)(20)(21). However, we did not rule out the possibility of substitution at the 5-position and hence decided to investigate this further.…”