Caffeine catalyzed synthesis of tetrahydrobenzo[b]pyran derivatives: Synthesis and insight into kinetics and mechanism.

Caffeine catalyzed synthesis of tetrahydrobenzo[b]pyran derivatives: Synthesis and insight into kinetics and mechanism.
Comb Chem High Throughput Screen. 2016 Oct 06;:
Authors: Habibi-Khorassani S, Shahraki M, Pourpanah SS, Mollashahi E, Keshavarz S
Abstract
In this work, synthesis and the feasibility of utilizing a modern in situ spectroscopic method (UV-vis spectrophotometry) has been demonstrated in order to investigate the reaction kinetics between arylaldehydes, malononitrile and dimedone in a mixture of ethanol and water as solvent in the presence of caffeine as a biodegradable catalyst. Attempts for mechanistic insight into the synthesis of a derivative of 4H-tetrahydrobenzo[b]pyrans included spectral kinetics approaches which revealed specific limiting conditions. The influence of various parameters (temperature, solvent and concentration) on the reaction by means of the pseudo-first order kinetic model was studied. Kinetic parameters were calculated. The initial stage of the presented mechanism is defined as a rate-determining step (k1) and is confirmed based upon the steady state approximation.
PMID: 27719623 [PubMed - as supplied by publisher]

Source: Combinatorial Chemistry and High Throughput Screening - October 5, 2016 Category: Chemistry Authors: Habibi-Khorassani S, Shahraki M, Pourpanah SS, Mollashahi E, Keshavarz S Tags: Comb Chem High Throughput Screen Source Type: research