The direct α-alkylation of ketones with alcohol to synthesize important α-alkylated ketones and enones is an attractive procedure for C–C bond formation. High reaction temperatures are always needed ...for heterogeneous catalysis using non-noble metals, and switching product selectivity in one catalysis system remains a great challenge. In the present study, a visible-light-driven procedure for this reaction is proposed, using oxidized TiN photocatalysts under mild conditions, whereby the product selectivity can be well-tuned. Oxidized TiN photocatalysts with tunable surface N/O ratios were successfully synthesized through the facile and flexible thermal oxidation treatment of low-cost TiN nanopowder. The α-alkylation of acetophenone with benzyl alcohol to form the two important compounds chalcone and dihydrochalcone occurred even at room temperature and almost complete conversion was achieved at 100 °C under visible light. The proportion of the two products can be well-tuned by switching the surface N/O ratio of the synthesized photocatalysts. Visible light is demonstrated to affect the surface N/O ratio of the photocatalysts and contribute to tuning the product selectivity. Light intensity and action spectrum study proves that the generation of energetic charge carriers results in the observed activities under visible light, based on interband transitions of TiN or the ligand-to-metal charge transfer (LMCT) effect of the surface complex formed on TiO2. Thermal energy can be coupled with light energy within this photocatalytic system, which will facilitate the full use of solar energy. Different sequential reaction mechanisms on TiN and TiO2 are proposed to be responsible for the tunable product selectivity. The wide reaction scope, the fine conversion at a low light intensity, and the favorable reusability of photocatalysts prove the great application potential of this visible-light-driven procedure for the α-alkylation of ketones with primary alcohols.
Owing to the wide and growing demand for primary alcohols, the development of efficient catalysts with high regioselectivity remains a worthwhile pursuit. However, according to Markovnikov's rule, it ...is a challenge to obtain primary alcohols with high yields and regioselectivity from terminal alkenes or alkynes. Herein, we report the synthesis of a photosensitizing two‐dimensional (2D) metal–organic framework (MOF) from cyclic trinuclear copper(I) units (Cu‐CTUs) and a boron dipyrro‐methene (Bodipy) ligand. The MOF features broadband light absorption, excellent photoinduced charge separation efficiency, and photochemical properties. By integrating the copper‐catalyzed hydroboration and photocatalyzed aerobic oxidation, it can catalyze terminal alkenes and alkynes to produce primary alcohols via a one‐pot tandem reaction with excellent regioselectivity, good overall yields in two‐step reactions (up to 85 %), broad substrate compatibility (32 examples) and good reusability under mild conditions.
A Cu‐CTU‐based photosensitizing covalent metal–organic framework (JNM‐20) was constructed. The MOF possessed broadband light absorption, excellent photoinduced charge‐separation efficiency, and photochemical properties, allowing the production of primary alcohols from terminal alkenes and alkynes with excellent anti‐Markovnikov selectivity, good overall yields, broad substrate compatibility, and good reusability via tandem catalysis.
A photosensitizing covalent metal–organic framework (CMOF) was prepared as a tandem reaction catalyst by Guo‐Hong Ning, Dan Li, and co‐workers in their Research Article (e202306497). By combining ...Cu‐CTUs as metal‐catalytic sites and Bodipy linkers as photosensitizers, this CMOF can catalyze terminal alkenes and alkynes to produce primary alcohols via one‐pot tandem reactions with excellent regioselectivity, good overall yields for two‐step reactions, broad substrate compatibility and good reusability under mild conditions.
A highly selective, efficient and practical method for synthesizing primary alcohols was presented. By using cheap Fe(BF4)2 ⋅ 6H2O and /tris2‐(diphenylphosphino)phenylphosphine (L1) as catalysts with ...formic acid as hydrogen source, a variety of primary alcohols bearing versatile functional groups could be obtained from both alkyl‐ and aryl‐substituted epoxides under mild conditions.
Highly selective and efficient synthesis of primary alcohols from epoxides could be achieved under mild conditions by iron catalysis, this process used formic acid as hydrogen source and was suitable for both alkyl‐ and aryl‐substituted epoxides.
The air-stable Ru(II) complex (I) has been synthesized by non-covalently interacting anionic Ru(p-cymene)Cl3 and 1,3-diisopropyl-1H-perimidin-2(3H)-iminium (LH2+). The compound was subjected to ...experimental evaluation to conduct TH reactions on aldehydes, ketones, and nitroarenes. The process entailed the utilization of ethanol, a hydrogen source that is both economically advantageous and ecologically benign.
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•The ruthenium(II) catalyst is remarkably resilient in the presence of moisture and oxygen.•The Ru(II) catalyst is used for the transfer hydrogenation of carbonyl compounds and nitroarenes.•The process involved using ethanol, a cost-effective and environmentally friendly H-source.•The control experiment demonstrated the formation of Ru-H species.•A plausible mechanism has been hypothesized, relying on stoichiometric investigations.
Isopropanol and formic acid are predominantly utilized as hydrogen sources in catalytic transfer hydrogenation reactions. However, the utilization of primary alcohols in such reactions has been sparsely documented, with only a limited number of reports available. In this article, we hereby present findings that underscore the prospective application of ecologically sustainable and economically viable ethanol, alongside a ruthenium(II) catalyst that exhibits remarkable resilience in the presence of moisture and oxygen. The air-stable Ru(II) complex (I) has been synthesized by non-covalently interacting anionic Ru(p-cymene)Cl3 and 1,3-diisopropyl-1H-perimidin-2(3H)-iminium (LH2+). The compound was subjected to experimental evaluation to conduct transfer hydrogenation reactions on aldehydes, ketones, and nitroarenes. The process entailed the utilization of ethanol, a hydrogen source that is both economically advantageous and ecologically benign. The hydrogen bond interaction existing between the Ru(p-cymene)Cl3 and LH2+ species plays a crucial in facilitating the exceptional catalytic efficiency exhibited by the Ru(II) complex (I). The reaction exhibits a wide range of substrate compatibility, enabling the hydrogenation of ketones, aldehydes, and nitroarenes. The results obtained from the control experiments have provided evidence for the formation of Ru − H species. A plausible mechanism has been hypothesized, relying on stoichiometric investigations.
Cuticular wax, forming the first line of defense against adverse environmental stresses, comprises very long-chain fatty acids (VLCFAs) and their derivatives. 3-Ketoacyl-CoA synthase (KCS) is a ...rate-limiting enzyme for VLCFA biosynthesis. In this study, we isolated KCS10, a KCS gene from alfalfa, and analyzed the effect of gene expression on wax production and drought stress in transgenic plants. MsKCS10 overexpression increased compact platelet-like crystal deposition and promoted primary alcohol biosynthesis through acyl reduction pathways in alfalfa leaves. Overexpression of MsKCS10 induced the formation of coiled-rodlet-like crystals and increased n-alkane content through decarbonylation pathways in tobacco and tomato fruits. Overexpression of MsKCS10 enhanced drought tolerance by limiting nonstomatal water loss, improving photosynthesis, and maintaining osmotic potential under drought stress in transgenic tobacco. In summary, MsKCS10 plays an important role in wax biosynthesis, wax crystal morphology, and drought tolerance, although the mechanisms are different among the plant species. MsKCS10 can be targeted in future breeding programs to improve drought tolerance in plants.
The vital importance of plant surface wax in protecting tissue from environmental stresses is reflected in the huge commitment of epidermal cells to cuticle formation. During cuticle deposition, a ...massive flux of lipids occurs from the sites of lipid synthesis in the plastid and the endoplasmic reticulum to the plant surface. Recent genetic studies in Arabidopsis have improved our understanding of fatty acid elongation and of the subsequent modification of the elongated products into primary alcohols, wax esters, secondary alcohols, and ketones, shedding light on the enzymes involved in these pathways. In contrast, the biosynthesis of alkanes is still poorly understood, as are the mechanisms of wax transport from the site of biosynthesis to the cuticle. Currently, nothing is known about wax trafficking from the endoplasmic reticulum to the plasma membrane, or about translocation through the cell wall to the cuticle. However, a first breakthrough toward an understanding of wax export recently came with the discovery of ATP binding cassette (ABC) transporters that are involved in releasing wax from the plasma membrane into the apoplast. An overview of our present knowledge of wax biosynthesis and transport and the regulation of these processes during cuticle assembly is presented, including the evidence for coordination of cutin polyester and wax production.
A simple, practical and gram-scale process for direct transformation of primary alcohols or silyl ethers to ammonium salts was developed. This method has the feathers of easy work-up (a simple ...filtration), mild condition, high yield, great practicality and robustness. And the application of the ammonium salts in Suzuki coupling reaction was also accomplished.
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•A simple, practical and gram-scale process for direct transformation of alcohols or silyl ethers to ammonium salts.•Easy work-up (a simple filtration), mild condition, high yield, great practicality and robustness.•Application of the ammonium salts in Suzuki coupling reaction.
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•Hexan-1-ol is the most efficient membrane fluidizer among other alcohols.•Hexan-1-ol induces expression of the same sets of genes as butanol and benzyl alcohol.•Antisense RNA ...regulation plays an important role in alcohol stress response.
Cyanobacteria are model photosynthetic prokaryotic organisms often used in biotechnology to produce biofuels including alcohols. The effect of alcohols on cyanobacterial cell physiology and specifically on membrane fluidity is poorly understood. Previous research on various primary aliphatic alcohols found that alcohols with a short hydrocarbon chain (C1-C3) do not affect expression of genes related to membrane physical state. In addition, less water-soluble alcohols with a hydrocarbon chain longer than C8 are found to have a reduced ability to reach cellular membranes hence do not drastically change membrane physical state or induce expression of stress-responsive genes. Therefore, hexan-1-ol (C6) is suggested to have the most profound effect on cyanobacterial membrane physical state. Here, we studied the effects of hexan-1-ol on the cyanobacterium Synechocystis sp. PCC 6803 transcriptome. The transcriptome data obtained is compared to the previously reported analysis of gene expression induced by benzyl alcohol and butan-1-ol. The set of genes whose expression is induced after exposure to all three studied alcohols is identified. The expression under alcohol stress for several general stress response operons is analyzed, and examples of antisense interactions of RNA are investigated.
The cuticle wax covering the plant surface is a whitish hydrophobic protective barrier in Chinese cabbage, and the epicuticular wax crystal deficiency normally has higher commodity value for a tender ...texture and glossy appearance. Herein, two allelic epicuticular wax crystal deficiency mutants,
and
, were obtained from the EMS mutagenesis population of a Chinese cabbage DH line 'FT'.
The cuticle wax morphology was observed by Cryo-scanning electron microscopy (Cryo-SEM) and the composition of wax was determined by GC-MS. The candidate mutant gene was found by MutMap and validated by KASP. The function of candidate gene was verified by allelic variation.
The mutants had fewer wax crystals and lower leaf primary alcohol and ester content. Genetic analysis revealed that the epicuticular wax crystal deficiency phenotype was controlled by a recessive nuclear gene, named Brwdm1. MutMap and KASP analyses indicated that
, encoding an alcohol-forming fatty acyl-CoA reductase, was the candidate gene for
. A SNP 2,113,772 (C to T) variation in the 6
exon of
in
led to the 262
amino acid substitution from threonine (T) to isoleucine (I), which existed in a rather conserved site among the amino acid sequences from Brwdm1 and its homologs. Meanwhile, the substitution changed the three-dimensional structure of Brwdm1. The SNP 2,114,994 (G to A) in the 10
exon of
in
resulted in the change of the 434
amino acid from valine (V) to isoleucine (I), which occurred in the STERILE domain. KASP genotyping showed that SNP 2,114,994 was co-segregated with glossy phenotype. Compared with the wild type, the relative expression of Brwdm1 was significantly decreased in the leaves, flowers, buds and siliques of wdm1.
These results indicated that
was indispensable for the wax crystals formation and its mutation resulted in glossy appearance in Chinese cabbage.
