Scalable Regioselective and Stereoselective Synthesis of Functionalized (E)-4-Iodobut-3-en-1-ols: Gram-Scale Total Synthesis of Fungal Decanolides and Derivatives

Abstract

A reliable protocol to synthesize both racemic and chiral (E)-4-iodobut-3-en-1-ols from aldehydes or epoxides, respectively, containing various aromatic and aliphatic substitutions has been established. The utility of these compounds was then demonstrated by providing access to known fungal decanolides as well as novel aromatic macrocycles. The protocol provided a gram-scale route to (-)-aspinolide A and (-)-5-epi-aspinolide A utilizing a catalytic Nozaki-Hiyama-Kishi reaction to close the macrolide in the final step in 65-84% yields.

Synthesis of Bridged N,O‐Heterocyclic 1,6‐Epoxybenzo[c]azocines via Migration‐Annulation Cascade Reaction of α‐Imino Rhodium Carbenes

“…Therefore, the reaction time had to be shortened. The most effective dosage of rhodium catalyst was proved to be 2 mol% (entries [16][17] and the most efficient concentration was 0.1 M (entries [18][19]. Therefore, the optimized reaction conditions for the generation of 7 a were established as indicated in entry 14.…”

“…Additional references cited within the Supporting Information. [16][17][18][19][20][21][22][23][24] The Supporting Information contains general information, procedures, data and NMR spectra and X-ray data.…”

A Protecting‐Group‐Free Synthesis of (−)‐Salvinorin A

“…achieved this transformation under indium‐mediated Barbier‐like conditions using stoichiometric amounts of (1 S ,2 R )‐(+)‐2‐amino‐1,2‐diphenylethanol as a chiral auxiliary [14a] . The groups of Evans [6a] and Prisinzano [14b] also converted 3‐furaldehyde ( 6 ) to homopropargylic alcohol 16 . However, four or five steps were needed, respectively.…”

Synthesis of Phosphonomethylated Bromoacetylfurans and Their Reactions with 1,3-Dicarbonyl Compounds

“…2-Bromacetylfuran is obtained by bromination of acetylfuran with bromine in diethyl ether or in a mixture of diethyl ether and dioxane [1][2][3]. 3-Bromoacetylfuran was synthesized by bromination of 3-acetylfuran with bromine in the mixtures of acetic acid and toluene, as well as by means of bromination with copper dibromide in the boiling mixture of chloroform and ethyl acetate [4,5]. Phosphorus-containing bromoacetylfurans have not yet been obtained.…”