Cyclopentene Synthesis by a Catalytic [3+2] Annulation of Donor‐Acceptor Cyclopropanes with Polarized Alkenes

Abstract

[3+2] Annulation of donor‐acceptor cyclopropanes with alkynes represents an efficient route to cyclopentenes. Here, we describe a new cyclopentene synthesis via Lewis acid‐catalyzed ring‐opening addition and intramolecular SNV reaction of donor‐acceptor cyclopropanes with alkenes. The reaction is carried out under the catalysis of Sc(OTf)3 by using polarized alkenes, namely α‐oxo ketene dithioacetals, as 2 C partners.

Structural diversity, hypothetical biosynthesis, chemical synthesis, and biological activity ofGanodermameroterpenoids

“…25). 67 (±)-Petchilactone A ( 106) and (±)-petchilactone B (107) with a 6/6/5/5 ring system were obtained from the fruiting bodies of G. petchii. 57 Except for the lactone, their similar 6/6/5 ring systems could be constructed via a nucleophilic addition from C-2 ′ to C-6 ′ , Wagner-Meerwein rearrangement reaction of 9 ′ -CH 3 from C-7 ′ to C-6 ′ , and the electrophilic addition of C-2 and C-7 ′ .…”

Recent Advances in the Catalytic Synthesis of the Cyclopentene Core

“…Another interesting reaction was developed by Wang and coworkers in 2020. [32] They report the synthesis of cyclopentenes 66 via ring opening addition and intermolecular nucleophilic vinylic substitution (S N V) reaction between donor-acceptor cyclopropanes 65 and α-oxo ketene dithioacetals 64 employing Sc(OTf) 3 as Lewis acid catalyst (Scheme 18). The reaction tolerated a wide range of functional groups.…”

Synthesis of (Het)aryl 2-(2-hydroxyaryl)cyclopropyl Ketones

“…During last decades donor-acceptor (D-A) cyclopropanes [1][2][3][4][5][6] attracted a significant attention of organic chemists due to the excellent combination of their availability and high reactivity toward diverse classes of reaction partners: nucleophiles [4,[7][8][9][10], electrophiles [11,12], radicals [13,14], dipolarophiles [15][16][17][18][19][20][21][22], dipoles [23][24][25], 1,3-dienes [26][27][28], etc. (Scheme 1a).…”