Chemistry of Vinylidenecyclopropanes

Abstract

SIOC, CAS). His research interest is in photochemistry, total synthesis of natural products, asymmetric synthesis, Morita-Baylis-Hillman reaction, and fixation of CO 2 using transition metal catalyst.

Catalytic Enantioselective Ring-Opening Reactions of Cyclopropanes

“…Vinylidenecyclopropanes (VDCPs) are a class of three-membered ring carbocycles bearing an allene group, resulting in a high strain energy (51 kcal mol –1 ) . With appropriate substituents, VDCPs are stable and were shown to be suitable substrates for enantioselective ring-opening transformations .…”

“…Finally, the last three sections will discuss special classes of cyclopropanes substituted with C–C unsaturations: Vinylcyclopropanes (section ), alkylidenecyclopropanes (section ), and vinylidenecyclopropanes (section ). The presence of the more reactive π systems opens the way for other types of transition-metal-based activations, which has been described in dedicated reviews, − none of them specific to asymmetric transformations however. Cyclopropenes have been only rarely used in asymmetric ring-opening transformations and are not covered in this review …”

A DFT study on the competing mechanisms of PPh3-catalyzed [3+3] and [3+2] annulations between 5-acetoxypenta-2,3-dienoate and 1C,3O-bisnucleophiles

“…At the different acid/base conditions, several kinds of [1,n]-proton shift processes including [1,2]-proton shift, [1,4]-proton shift and [1,5]-proton shift are involved in the above annulation processes. Our annulation reaction channels are hard to occur without any protic media-assisted proton transfer, that is to say, pathways a and a are impossible to occur at the experimental condition.…”

“…Phosphines, which have been recognized as a remarkable Lewis base catalyst [1], have shown great potential for helping facilitate annulation reactions [2][3][4][5]. Since Zhang and Lu report the first phosphine-catalyzed [3 + 2] annulation reaction of 2,3-butadienoates and imines (or alkenes) in 1995 [6], organophosphine has been employed as a favorable catalyst for chemists to obtain a wide array of cyclic product from simple building block [2,[7][8][9][10][11][12][13][14][15][16][17][18][19].…”

Oxidative radical ring-opening/cyclization of cyclopropane derivatives

“…Cyclopropane derivatives, with their three-membered carbocyclic frameworks, have spurred considerable attention especially in the domain of organic and pharmaceutical synthesis because of their highly strained three-membered carbocyclic skeletons and their easy availability [1–16]. The cyclopropane derivatives, especially methylenecyclopropanes [17–21], cyclopropyl olefins [22] and cyclopropanols [23–24] undergo ring-opening/cyclization reactions to provide a huge number of fascinating compounds with different functional groups [25–31]. However, most recently reported methods usually proceed via a radical pathway.…”