Tandem Suzuki Coupling/Intramolecular Oxetane Ring Opening to Form Polycyclic Ring Systems

Abstract

A tandem one-pot reaction featuring a cross-coupling followed by an intramolecular oxetane ring opening by mild nucleophiles is reported. The overall transformation comprises a carbon−carbon bond formation along with a carbon−heteroatom bond construction providing diverse multicyclic ring systems with a pendant hydroxymethyl handle for further elaboration. This approach constitutes a convergent method for rapid access to various scaffolds. Furthermore, a comparison of computed low-energy conformers is presented to rationalize instances in which cyclization was not observed.

Synthesis of Ladder-Type 9,9′-Bifluorenylidene-Based Conjugated Oligomers via a Pd-Catalyzed Tandem Suzuki Coupling/Heck Cyclization Approach

“…6 Kuduk and co-workers used tandem Suzuki coupling/intramolecular oxetane ring opening to prepare polycyclic systems. 7 Rosei and co-workers reported the tandem desulfurization/C− C coupling reaction for synthesis of the pentacene and an exotic ladder polymer. 8 These studies demonstrated that tandem reactions can provide high efficiency and selectivity in the synthesis of compounds or polymers.…”

Tandem Amination/Oxetane Ring Opening toward Benzomorpholines

“…This approach would allow for selective formation of the desired regioisomer based on the selection of the aryl halide starting material. Aligned with our previous work on one-pot reactions employing the ring opening of oxetanes under basic conditions, , herein we report a tandem C–N coupling followed by oxetane ring opening to access benzomorpholine and tetrahydroquinoxaline scaffolds. In addition to the generation of these valuable heterocyclic motifs, a pendant hydroxymethyl group is revealed for further derivatization.…”

Oxetan-3-ols as 1,2-bis-Electrophiles in a Brønsted-Acid-Catalyzed Synthesis of 1,4-Dioxanes

“… 11 , 12 This intramolecular cyclization strategy has been successfully employed for the synthesis of heterocycles from prefunctionalized oxetane intermediates. 13 , 14 In particular, Sun has exploited this in the enantioselective syntheses of heterocycle derivatives employing a chiral phosphoric acid catalyst. This has included the enantioselective synthesis of 1,4-dioxanes from preformed hydroxy-ether-containing oxetanes ( Figure 1 C).…”