Synthesis of dibenzo[a,d]cycloheptanoids via aryne insertion into 2-arylidene-1,3-indandiones

Abstract

A cascade synthetic strategy for the direct synthesis of dibenzo[a,d]cycloheptanoids and dibenz[a,c]anthracene-9,14-dione derivatives from aryne precursors has been developed.

o-Silylaryl Triflates: A Journey of Kobayashi Aryne Precursors

“…Recently, Yennam and co-workers reported an unusual cascade process by treating 2-arylidene-1,3-indandiones 9-30 bearing electron-rich functional groups with arynes, affording dibenz­[ a , c ]­anthracene-9,14-dione derivatives 9-31 through a Diels–Alder reaction/ring expansion process (Scheme ). Mechanistically, after the Diels–Alder reaction to generate cycloadduct 9-32 , alcohol intermediate 9-33 could be formed via an intramolecular nucleophilic addition on 9-32 , which then experiences a retro-aldol reaction to furnish product 9-31 . Interestingly, when R 1 is an electron-poor substituent on 9-30 , a C–C bond insertion/ring expansion transformation occurred, affording dibenzo­[ a , d ]­cycloheptanoid analogues 9-34 in moderate to high yields.…”

“…163) 650. Mechanistically, after the Diels−Alder reaction to generate cycloadduct 9-32, alcohol intermediate 9-33 could be formed via an intramolecular nucleophilic addition on 9-32, which then experiences a retro-aldol reaction to furnish product 9-31.…”

A Method to Access Highly Functionalized Dibenzobicyclo[3.2.1]octadienones: Application to the Construction of the 6/6/5/6/6 Carbon Skeleton of Rubialatin A

“…7 Insertion of arynes into activated C−C, C− X, and C−H bonds and other common heterocyclic compounds has been an active area of research for many groups across the globe. 8 In particular, cyclic-1,3-dicarbonyl insertion via acylalkylation of aryne on β-ketoesters through a σ-bond has been researched by Stoltz's group, 9 insertion into the C−C bond of cyclic 1,3-diketones by Mehta et al, 10 and insertion on 2arylidene-1,3-indandiones by Yennam et al 11 (Scheme 2), which have inspired us to further investigate the aryne insertion into 2-phenacyl-1,3-indandiones and related compounds.…”

Domino reaction of bindone and 1,3-dipolarophiles for the synthesis of diverse spiro and fused indeno[1,2-a]fluorene-7,12-diones

“…In order to explain the formation of this unique polycyclic spiro compound 8 , a domino reaction mechanism was briefly proposed as shown in Scheme 3 based on the present experiments and the previous related works. 12 a ,15 Firstly, a base catalyzed condensation of two molecules of 1,3-indandione gave the desired bindone 1 through the intermediate ( H ). In the meantime, base catalyzed aldol condensation of 1,3-indandione and isatin afforded the adduct ( I ), which in turn converted to isatylidene 1,3-indanedione ( J ).…”