17699-09-1Relevant articles and documents
Influence of a hydroxy group in the asymmetric reduction of selenides: Enantioselective synthesis of naturally occurring monoterpenes
Ceccherelli, Paolo,Curini, Massimo,Epifano, Francesco,Marcotullio, Maria Carla,Rosati, Ornelio
, p. 919 - 922 (1998)
The reductive cleavage of the benzenseleno-group in trans-β- hydroxyselenides, to yield a stereogenic methyne center, has been investigated. When the reaction is carried out with lithium in diethylamine, the equilibrated carbanionic intermediate traps the proton of the neighbouring hydroxy function, blocking the stereogenic center as a product with a predictable chirality. Using this strategy, several natural monoterpenes in enantiomerically pure form have been prepared.
From Bugs to Bioplastics: Total (+)-Dihydrocarvide Biosynthesis by Engineered Escherichia coli
Ascue Avalos, Gabriel A.,Toogood, Helen S.,Tait, Shirley,Messiha, Hanan L.,Scrutton, Nigel S.
, p. 785 - 792 (2019)
The monoterpenoid lactone derivative (+)-dihydrocarvide ((+)-DHCD) can be polymerised to form shape-memory polymers. Synthetic biology routes from simple, inexpensive carbon sources are an attractive, alternative route over chemical synthesis from (R)-carvone. We have demonstrated a proof-of-principle in vivo approach for the complete biosynthesis of (+)-DHCD from glucose in Escherichia coli (6.6 mg L?1). The pathway is based on the Mentha spicata route to (R)-carvone, with the addition of an ′ene′-reductase and Baeyer–Villiger cyclohexanone monooxygenase. Co-expression with a limonene synthesis pathway enzyme enables complete biocatalytic production within one microbial chassis. (+)-DHCD was successfully produced by screening multiple homologues of the pathway genes, combined with expression optimisation by selective promoter and/or ribosomal binding-site screening. This study demonstrates the potential application of synthetic biology approaches in the development of truly sustainable and renewable bioplastic monomers.
MICELLAR PERTURBATION OF ENONE REDUCTION
Nikles, Jacqueline A.,Sukenik, Chaim N.
, p. 4211 - 4214 (1982)
The reduction of several enones using BH4(1-) in the presence of cationic surfactants has been investigated.These reductions are all shifted by the micelle towards the formation of conjugate reduction products.
Synthesis of optically active dihydrocarveol via a stepwise or one-pot enzymatic reduction of (R)- and (S)-carvone
Chen, Xi,Gao, Xiuzhen,Wu, Qiaqing,Zhu, Dunming
, p. 734 - 738 (2012)
A recombinant enoate reductase LacER from Lactobacillus casei catalyzed the reduction of (R)-carvone and (S)-carvone to give (2R,5R)-dihydrocarvone and (2R,5S)-dihydrocarvone with 99% and 86% de, respectively, which were further reduced to dihydrocarveols by a carbonyl reductase from Sporobolomyces salmonicolor SSCR or Candida magnolia CMCR. For (R)-carvone, (1S,2R,5R)-dihydrocarveol was produced as the sole product with >99% conversion, while (1S,2R,5S)-dihydrocarveol was obtained as the major product, but with a lower de when (S)-carvone was used as the substrate. The one-pot reduction was performed at a 0.1 M substrate concentration, indicating that it might provide an effective synthetic route to this type of chiral compound.
THE BIOTRANSFORMATION OF CARVOXIME AND DEHYDROCARVOXIME WITH CELL SUSPENSION CULTURES OF NICOTIANA TABACUM
Suga, Takayuki,Hirata, Toshifumi,Futatsugi, Masayuki
, p. 1327 - 1328 (1984)
In newly initiated cell suspension cultures of Nicotiana tabacum (4R)-(-)-and (4S)-(+)-carvoximes and (1S,4R)-(+)-dihydrocarvoxime were hydrolysed to the corresponding ketones and then the resultant ketones were reduced to the corresponding alcohols.Key words: Nicotiana tabacum; Solanaceae; tissue culture; biotransformation; hydrolysis; carvoxime; dihydrocavoxime.
REDUCTION OF CARBONYL COMPOUNDS VIA HYDROSILYLATION. V. SYNTHESIS OF OPTICALLY ACTIVE ALLYLIC ALCOHOLS VIA REGIOSELECTIVE ASYMMETRIC HYDROSILALATION
Kogure, Tetsuo,Ojima, Iwao
, p. 249 - 256 (1982)
Regioselective asymmetric reduction of prochiral α,β-unsaturated ketones to optically active allylic alcohols was performed via hydrosilylation catalyzed by a rhodium(I) complex with (+)-BMPP, (+)-DIOP and (-)-DIOP as chiral ligands.The allylic alcohols with optical purity up to 69percent e.e. were obtained in good yields.The extent of asymmetric induction was found to depend on the stereoelectronic matching of the chiral ligand, ketone and hydrosilane employed.In the asymmetric reduction of (R)-carbone, leading to carveol, the extent of asymmetric induction was found todepend markedly on the ligand/rhodium ratio.Either trans-(5R,1S)-carveol or cis-(5R,1R)-carveol was obtained with good stereoselectivity by using (-)-DIOP or (+)-DIOP as chiral ligand, and it turned out that the chiral center present in carbone had only a slight influence on the asymmetric induction by the chiral catalysts.
New fungi for whole-cell biotransformation of carvone enantiomers. Novel p-menthane-2,8,9-triols production
Nunes, Fátima M.,Dos Santos, Gabriel F.,Saraiva, Natália N.,Trapp, Marília A.,De Mattos, Marcos C.,Oliveira, Maria Da Concei??o F.,Rodrigues-Filho, Edson
, p. 88 - 94 (2013)
The microbial biotransformation of carvone enantiomers by Lasiodiplodia theobromae, Trichoderma harzianum and Mucor circinelloides was investigated. Biotransformation experiments were conducted using growing or resting fungi cells and the products were an
Heterogeneous Hydroxyl-Directed Hydrogenation: Control of Diastereoselectivity through Bimetallic Surface Composition
Shumski, Alexander J.,Swann, William A.,Escorcia, Nicole J.,Li, Christina W.
, p. 6128 - 6134 (2021/05/29)
Directed hydrogenation, in which product selectivity is dictated by the binding of an ancillary directing group on the substrate to the catalyst, is typically catalyzed by homogeneous Rh and Ir complexes. No heterogeneous catalyst has been able to achieve equivalently high directivity due to a lack of control over substrate binding orientation at the catalyst surface. In this work, we demonstrate that Pd-Cu bimetallic nanoparticles with both Pd and Cu atoms distributed across the surface are capable of high conversion and diastereoselectivity in the hydroxyl-directed hydrogenation reaction of terpinen-4-ol. We postulate that the OH directing group adsorbs to the more oxophilic Cu atom while the olefin and hydrogen bind to adjacent Pd atoms, thus enabling selective delivery of hydrogen to the olefin from the same face as the directing group with a 16:1 diastereomeric ratio.
Methylene-Linked Bis-NHC Half-Sandwich Ruthenium Complexes: Binding of Small Molecules and Catalysis toward Ketone Transfer Hydrogenation
Botubol-Ares, José Manuel,Cordón-Ouahhabi, Safa,Moutaoukil, Zakaria,Collado, Isidro G.,Jiménez-Tenorio, Manuel,Puerta, M. Carmen,Valerga, Pedro
supporting information, p. 792 - 803 (2021/04/06)
The complex [Cp*RuCl(COD)] reacts with LH2Cl2 (L = bis(3-methylimidazol-2-ylidene)) and LiBun in tetrahydrofuran at 65 °C furnishing the bis-carbene derivative [Cp*RuCl(L)] (2). This compound reacts with NaBPh4 in MeOH under dinitrogen to yield the labile dinitrogen-bridged complex [{Cp*Ru(L)}2(μ-N2)][BPh4]2 (4). The dinitrogen ligand in 4 is readily replaced by a series of donor molecules leading to the corresponding cationic complexes [Cp*Ru(X)(L)][BPh4] (X = MeCN 3, H2 6, C2H4 8a, CH2CHCOOMe 8b, CHPh 9). Attempts to recrystallize 4 from MeNO2/EtOH solutions led to the isolation of the nitrosyl derivative [Cp*Ru(NO)(L)][BPh4]2 (5), which was structurally characterized. The allenylidene complex [Cp*Ru═C═C═CPh2(L)][BPh4] (10) was also obtained, and it was prepared by reaction of 2 with HCCC(OH)Ph2 and NaBPh4 in MeOH at 60 °C. Complexes 3, 4, and 6 are efficient catalyst precursors for the transfer hydrogenation of a broad range of ketones. The dihydrogen complex 6 has proven particularly effective, reaching TOF values up to 455 h-1 at catalyst loadings of 0.1% mol, with a high functional group tolerance on the reduction of a broad scope of aryl and aliphatic ketones to yield the corresponding alcohols.
Efficient Transfer Hydrogenation of Ketones using Methanol as Liquid Organic Hydrogen Carrier
Garg, Nidhi,Paira, Soumen,Sundararaju, Basker
, p. 3472 - 3476 (2020/05/29)
Herein, we demonstrate an efficient protocol for transfer hydrogenation of ketones using methanol as practical and useful liquid organic hydrogen carrier (LOHC) under Ir(III) catalysis. Various ketones, including electron-rich/electron-poor aromatic ketones, heteroaromatic and aliphatic ketones, have been efficiently reduced into their corresponding alcohols. Chemoselective reduction of ketones was established in the presence of various other reducible functional groups under mild conditions.