Light-induced access to gram-scale photosynthesis of polyfunctionalized dihydro-2-oxypyrroles: A recyclable halide perovskite photocatalyst as a single-electron redox mediator for radical-initiated Michael-Mannich cyclocondensation in air atmosphere

Abstract

A sustainable method of photosynthesis was developed for the synthesis of polyfunctionalized dihydro-2-oxypyrroles by employing the Michael-Mannich cyclocondensation of amines, dialkyl acetylenedicarboxylates, and formaldehyde. With the aim of utilizing a renewable energy source and air atmospheric conditions at room temperature, the utilization of a photocatalyst as a single-electron redox mediator in an ethanol solution under blue light exposure was adopted. The objective of the ongoing study is to use and advance a halide perovskite that is widely accessible, recyclable, and economically viable. The halide perovskite, CsPbBr3, offers significant advantages in terms of time-saving properties, easy handling techniques, exceptional yield, energy preservation, and environmental friendliness. The previously mentioned occurrence enables the monitoring of the progression and alteration of environmental and chemical conditions over time. The concept that this chemical procedure can be efficiently and reliably employed in industrial settings is supported by the empirical evidence acquired from cyclization at the gram-scale magnitude. The turnover number (TON) and turnover frequency (TOF) of polyfunctionalized dihydro-2-oxypyrroles were determined through investigation. Moreover, the simplicity of utilization of CsPbBr3 is a crucial advantage of our research. With a minimum of 5 runs demonstrating no decline in catalytic activity, this halide perovskite showcases a lengthy lifespan of use, offering a remarkable economic characteristic. The novel approach presents a practical technique for harnessing perovskite materials, which possess elevated catalytic activity and stability. As a heterogeneous photocatalyst, this halide perovskite possesses the capability to achieve the desired outcomes of efficient photocatalytic reactions.