Gold(I)‐Catalyzed Tandem Transformation with Diynes: Rapid Access to Linear Cyclopentenone‐Fused Polycyclic Molecules

Abstract

An efficient and convenient synthesis of useful linear cyclopentenone-fused polycyclic compounds has been achieved through a novel gold(I)-catalyzed transformation of diynes. The method demonstrates high product yields and tolerates of a wide variety of important functional groups. Gold-vinylidene formation, methoxy group migration, and Nazarov-type cyclization are proposed to be the key steps in the reaction pathway. The synthetic utility of this method is demonstrated by converting the product to eight-membered-ring-fused compound.

Gold-Catalyzed Formal Hexadehydro-Diels–Alder/Carboalkoxylation Reaction Cascades

“…On the basis of the above-described results together with the results of previous studies, ,, we suggest that the gold catalyst plays two roles during this cascade reaction. First, its involvement in the HDDA process results in the mechanism switching from a diradical pathway to a cationic pathway.…”

“…Recently, dual gold catalysis has emerged as a powerful tool for de novo synthesis of aromatic rings. Gagosz and our research group independently reported dual gold-catalyzed tetradehydro-Diels–Alder (TDDA) reactions of dienynes to form carbazoles and indolines.…”

Gold Vinylidenes as Useful Intermediates in Synthetic Organic Chemistry

“…Intramolecular transfers of alkoxy groups to gold vinylidene species is also feasible as reported by the Zhang group. 40 When aryl diynes 102 possessing a methoxy group at the propargylic position were reacted with a catalytic amount of [(IPr)Au]NTf 2 in a t-BuOH/DCE mixture at 70 °C, various polyclic fused cylopentenones 106 could be obtained (Scheme 25). To explain their formation, the authors proposed that a transfer of the methoxy group from the allylic position to the gold vinylidene moiety could proceed in the intermediately formed species 103.…”

Dual Gold‐Catalyzed Three‐Component Reaction: Efficient Synthesis of Indene‐Fused Esters, Acids, and Lactones through Gold Vinylidene Intermediates

“…In several early studies, gold vinylidenes were proposed as reactive intermediates that underwent facile C–H or Nu–H insertion [Equation (1)]. Only a few reports appeared in which a gold vinylidene was trapped with one nucleophile such as water or a methoxy group [Equation (2)]. In line with our interests in exploring new reactivities of Au vinylidenes, we continue to be inspired by other metal vinylidene complexes such as Ru, Rh, and W .…”