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• 1004-77-9 2-isopropylcyclohexanone 

Relevant academic research and scientific papers

MMPP (Magnesium Monoperoxyphthalate) in acetonitrile; a new approach to the synthesis of lactones via Baeyer-Villiger oxidation of cyclic ketones

A variety of unsubstituted and mono- or di-substituted cycloalkanones can be oxidised with modest excess of magnesium monoperoxyphthalate hexahydrate in acetonitrile to produce the corresponding lactones in facile, selective, and high yielding manner.

Continuous Production of Biorenewable, Polymer-Grade Lactone Monomers through Sn-Β-Catalyzed Baeyer–Villiger Oxidation with H2O2

The Baeyer–Villiger oxidation is a key transformation for sustainable chemical synthesis, especially when H2O2 and solid materials are employed as oxidant and catalyst, respectively. 4-substituted cycloketones, which are readily available from renewables, present excellent platforms for Baeyer–Villiger upgrading. Such substrates exhibit substantially higher levels of activity and produce lactones at higher levels of lactone selectivity at all values of substrate conversion, relative to non-substituted cyclohexanone. For 4-isopropyl cyclohexanone, which is readily available from β-pinene, continuous upgrading was evaluated in a plug-flow reactor. Excellent selectivity (85 % at 65 % conversion), stability, and productivity were observed over 56 h, with over 1000 turnovers (mol product per mol Sn) being achieved with no loss of activity. A maximum space–time yield that was almost twice that for non-substituted cyclohexanone was also obtained for this substrate [1173 vs. 607 g(product) kg(catalyst)?1 cm?3 h?1]. The lactone produced is also shown to be of suitable quality for ring opening polymerization. In addition to demonstrating the viability of the Sn-β/H2O2 system to produce renewable lactone monomers suitable for polymer applications, the substituted alkyl cyclohexanones studied also help to elucidate steric, electronic, and thermodynamic elements of this transformation in greater detail than previously achieved.

Laboratory evolution of robust and enantioselective Baeyer-Villiger monooxygenases for asymmetric catalysis

The Baeyer-Villiger Monooxygenase, Phenylacetone Monooxygenase (PAMO), recently discovered by Fraaije, Janssen, and co-workers, is unusually thermostable, which makes it a promising candidate for catalyzing enantioselective Baeyer-Villiger reactions in organic chemistry. Unfortunately, however, its substrate scope is very limited, reasonable reaction rates being observed essentially only with phenylacetone and similar linear phenyl-substituted analogs. Previous protein engineering attempts to broaden the range of substrate acceptance and to control enantioselectivity have been met with limited success, including rational design and directed evolution based on saturation mutagenesis with formation of focused mutant libraries, which may have to do with complex domain movements. In the present study, a new approach to laboratory evolution is described which has led to mutants showing unusually high activity and enantioselectivity in the oxidative kinetic resolution of a variety of 2-aryl and 2-alkylcyclohexanones which are not accepted by the wild-type (WT) PAMO and of a structurally very different bicyclic ketone. The new strategy exploits bioinformatics data derived from sequence alignment of eight different Baeyer-Villiger Monooxygenases, which in conjunction with the known X-ray structure of PAMO and induced fit docking suggests potential randomization sites, different from all previous approaches to focused library generation. Sites harboring highly conserved proline in a loop of the WT are targeted. The most active and enantioselective mutants retain the high thermostability of the parent WT PAMO. The success of the "proline" hypothesis in the present system calls for further testing in future laboratory evolution studies.