694502-98-2Relevant academic research and scientific papers
Microbial Baeyer-Villiger oxidation: Stereopreference and substrate acceptance of cyclohexanone monooxygenase mutants prepared by directed evolution
Mihovilovic, Marko D.,Rudroff, Florian,Winninger, Alexander,Schneider, Toni,Schulz, Frank,Reetz, Manfred T.
, p. 1221 - 1224 (2006)
An array of random mutants of cyclohexanone monooxygenase (CHMO) from Acinetobacter sp. NCIMB 9871 was screened against a library of structurally diverse ketones for modifications in the substrate acceptance profile and stereopreference of the enzymatic B
A Proton-Responsive Pyridyl(benzamide)-Functionalized NHC Ligand on Ir Complex for Alkylation of Ketones and Secondary Alcohols
Kaur, Mandeep,U Din Reshi, Noor,Patra, Kamaless,Bhattacherya, Arindom,Kunnikuruvan, Sooraj,Bera, Jitendra K.
supporting information, p. 10737 - 10748 (2021/06/15)
A Cp*Ir(III) complex (1) of a newly designed ligand L1 featuring a proton-responsive pyridyl(benzamide) appended on N-heterocyclic carbene (NHC) has been synthesized. The molecular structure of 1 reveals a dearomatized form of the ligand. The protonation of 1 with HBF4 in tetrahydrofuran gives the corresponding aromatized complex [Cp*Ir(L1H)Cl]BF4 (2). Both compounds are characterized spectroscopically and by X-ray crystallography. The protonation of 1 with acid is examined by 1H NMR and UV-vis spectra. The proton-responsive character of 1 is exploited for catalyzing α-alkylation of ketones and β-alkylation of secondary alcohols using primary alcohols as alkylating agents through hydrogen-borrowing methodology. Compound 1 is an effective catalyst for these reactions and exhibits a superior activity in comparison to a structurally similar iridium complex [Cp*Ir(L2)Cl]PF6 (3) lacking a proton-responsive pendant amide moiety. The catalytic alkylation is characterized by a wide substrate scope, low catalyst and base loadings, and a short reaction time. The catalytic efficacy of 1 is also demonstrated for the syntheses of quinoline and lactone derivatives via acceptorless dehydrogenation, and selective alkylation of two steroids, pregnenolone and testosterone. Detailed mechanistic investigations and DFT calculations substantiate the role of the proton-responsive ligand in the hydrogen-borrowing process.
First chemo-enzymatic synthesis of the (R)-Taniguchi lactone and substrate profiles of CAMO and OTEMO, two new Baeyer–Villiger monooxygenases
Rudroff, Florian,Fink, Michael J.,Pydi, Ramana,Bornscheuer, Uwe T.,Mihovilovic, Marko D.
, p. 157 - 165 (2017/01/17)
Abstract: This study investigates the substrate profile of cycloalkanone monooxygenase and 2-oxo-Δ3-4,5,5-trimethylcyclopentenylacetyl-coenzyme A monooxygenase, two recently discovered enzymes of the Baeyer–Villiger monooxygenase family, used as whole-cell biocatalysts. Biooxidations of a diverse set of ketones were performed on analytical scale: desymmetrization of substituted prochiral cyclobutanones and cyclohexanones, regiodivergent oxidation of terpenones and bicyclic ketones, as well as kinetic resolution of racemic cycloketones. We demonstrated the applicability of the title enzymes in the enantioselective synthesis of (R)-(?)-Taniguchi lactone, a building block for the preparation of various natural product analogs such as ent-quinine. Graphical abstract: [Figure not available: see fulltext.]
Synthesis and insecticidal activity of lactones derived from furan-2(5H)-one
Teixeira, Milena G.,Alvarenga, Elson S.,Pimentel, Mirian F.,Pican?o, Marcelo C.
, p. 2279 - 2289 (2015/11/10)
Ten 4,7-methanoisobenzofuran-1(3H)-ones were synthesized and their insecticidal activities against the insect pest Diaphania hyalinata were evaluated. The most active substances have been selected from the initial screening to find the dose to kill 50 (LD50) and 90percent (LD90) of the melonworm. Time-mortality curves of the three selected formulations at the LD90 concentration have been made against D. hyalinata. From the time-mortality curves we found that the formulation (3aR,4R,5S,6S,7S,7aS)- and (3aS,4S,5R,6R,7R,7aR)-5,6-dichlorohexahydro-4,7-methanoisobenzofuran-1(3H)-one + (3aR,4R,5R,6R,7S,7aS)- and (3aS,4S,5S,6S,7R,7aR)-5,6-dichlorohexahydro-4,7-methanoisobenzofuran-1(3H)-one has killed 50percent of the melonworm after 2 h, presenting the best knockdown effect. Bioassays against Solenopsis saevissima and Tetragonisca angustula were carried out for the lactones selected in the initial screening against D. hyalinata. The formulation (3aS,4R,5S,6S,7S,7aR)- and (3aR,4S,5R,6R,7R,7aS)-5,6-dibromohexahydro-4,7-methanoisobenzofuran-1(3H)-one + (3aS,4R,5R,6R,7S,7aR)- and (3aR,4S,5S,6S,7R,7aS)-5,6-dibromohexahydro-4,7-methanoisobenzofuran-1(3H)-one has killed 31.25 and 68.30percent of the pest natural enemy and the pollinator bee, respectively. At the same concentration this formulation killed 90percent of D. hyalinata. The selectivity in favor of the non-target organisms has rendered this formulation a position as a promising agrochemical.
Facile organocatalytic domino oxidation of diols to lactones by in situ-generated TetMe-IBX
Jhulki, Samik,Seth, Saona,Mondal, Manas,Moorthy, Jarugu Narasimha
, p. 2286 - 2293 (2014/03/21)
The domino oxidation of diols to lactones is an important transformation, and catalytic protocols that allow this conversion smoothly are scarce. Capitalizing on the established reactivity of tetramethyl-IBX (TetMe-IBX) and its in situ generation in the presence of a co-oxidant, such as oxone, we have shown that a variety of diols can be converted to the corresponding lactones in respectable yields by employing the precursor of TetMe-IBX, namely, tetramethyl-o-iodobenzoic acid (TetMe-IA), as a catalyst in 5 mol % in the presence of 2 equiv of oxone.
Catalytic enantioselective desymmetrization of meso cyclic anhydrides via iridium-catalyzed hydrogenation
Liu, Tang-Lin,Li, Wei,Geng, Huiling,Wang, Chun-Jiang,Zhang, Xumu
supporting information, p. 1740 - 1743 (2013/06/27)
A novel method to desymmetrize meso-anhydrides into lactones via asymmetric hydrogenation catalyzed by the Ir-C3*-TunePhos complex has been developed. Various chiral lactones were synthesized with full conversion and excellent enantioselectivit
Self-sufficient Baeyer-Villiger monooxygenases: Effective coenzyme regeneration for biooxygenation by fusion engineering
Torres Pazmino, Daniel E.,Snajdrova, Radka,Baas, Bert-Jan,Ghobrial, Michael,Mihovilovic, Marko D.,Fraaije, Marco W.
supporting information; scheme or table, p. 2275 - 2278 (2009/02/08)
(Chemical Presented) Two-in-one biocatalysts were engineered by the covalent fusion of NADPH-dependent Baeyer-Villiger monooxygenases to a phosphite dehydrogenase for coenzyme regeneration (see scheme). Not only the purified fusion proteins, but also whole cells and crude cell extracts containing the enzyme conjugates, could be used to catalyze biotransformations with high efficiency. NADP+=nicotinamide adenine dinucleotide phosphate.
An efficient oxidative lactonization of 1,4-diols catalyzed by Cp*Ru(PN) complexes
Ito, Masato,Osaku, Akihide,Shiibashi, Akira,Ikariya, Takao
, p. 1821 - 1824 (2008/02/02)
An efficient oxidative lactonization of 1,4-diols in acetone is accomplished by the well-defined ruthenium catalyst, whose bifunctional nature underlies the high efficiency as well as unique chemo- and regioselectivity of the reaction which provides a rapid access to γ-butyrolactones including flavor lactones hinokinin, and muricatacin.
Catalytic asymmetric oxidative lactonizations of meso-diols using a chiral iridium complex
Suzuki, Takeyuki,Morita, Kenji,Matsuo, Yoshimi,Hiroi, Kunio
, p. 2003 - 2006 (2007/10/03)
A chiral amino alcohol/Ir complex catalyzes the asymmetric oxidative lactonizations of meso-diols to give the corresponding lactones in up to 81% ee.
Preparation of a Promising Cyclobutanone Chiral Building Block: Its Stereochemistry and Utilization
Taniguchi, Takahiko,Goto, Yasuo,Ogasawara, Kunio
, p. 707 - 709 (2007/10/03)
A cyclobutanone possessing a bicyclo[2.2.1]heptene framework {endo-tricyclo[4.2.1.02,5]non-7-en-3-one} has been prepared in both enantiomeric forms employing lipase-mediated kinetic resolution as the key step. To determine the absolute configuration, as well as to demonstrate the synthetic potential, both enantiomers of the cyclobutanone obtained have been transformed enantioconvergently into the key intermediate of the sesquiterpene (+)-β-santalene and the iridoid monoterpene (-)-boschnialactone.
