The Synthesis of Tris‐Annulated Benzenes by Aldol Trimerization of Cyclic Ketones

Abstract

For the synthesis of tris-annulated benzene rings, the aldol trimerization of cyclic ketones has been known as a powerful tool since the 19 th century. Why the reaction works so well with some ketones (e.g., indanone) but fails so miserably with others (e.g., tetralone), however, has never been adequately explained. This chapter outlines the development and scrutiny of a hypothesis that says: formation of an a,b-unsaturated (conjugated) dimer from a cyclic ketone is vital to the success of an aldol trimerization reaction for the synthesis of a tris-annulated benzene; the reaction will fail with ketones that form only b,g-unsaturated (unconjugated) dimers. This hypothesis unifies much experimental chemistry and is supported by theoretical calculations.

Site-selective covalent functionalization at interior carbon atoms and on the rim of circumtrindene, a C36H12 open geodesic polyarene

“…Cyclotrimerization of 17 to the C 3 -symmetric trichlorodecacyclene 12 was accomplished by a triple aldol condensation of the chloro ketone 17 [48–49]. Improvements in the procedures reported previously are described in the experimental section in the Supporting Information File 1.…”

“…The halogenated FVP precursor, 3,9,15-trichlorodecacyclene ( 12 ), was prepared in five steps from commercially available starting materials, following the same route reported in our earlier publication ( Scheme 4 ) [ 20 ]. Cyclotrimerization of 17 to the C 3 -symmetric trichlorodecacyclene 12 was accomplished by a triple aldol condensation of the chloro ketone 17 [ 48 – 49 ]. Improvements in the procedures reported previously are described in the experimental section in the Supporting Information File 1 .…”

Diazatriphenylenes and their thiophene analogues: synthesis and applications

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] In this series triphenylenes [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37] and their thiophene analogues (viz. phenanthro [9,10- A first-rate review on the chemistry of the above mentioned heteroaromatic systems, focusing on their synthesis, electronic properties, and applications in materials science, has recently been published.…”

Atmosphere-Controlled Palladium-Catalyzed Divergent Decarboxylative Cyclization of 2-Iodobiphenyls and α-Oxocarboxylic Acids

“…In the past few decades, polycyclic aromatic hydrocarbons (PAHs) have received considerable attention due to their intriguing chemical, electronic, and photophysical properties . Tribenzotropone derivatives have emerged as a common precursor for the construction of heptagon-embedded PAHs .…”