66997-68-0

Upstream product

• 76835-64-8 methyl 3-oxododecanoate 
• 112-12-9 methyl nonyl ketone 
• 112-13-0 n-decanoyl chloride 
• 182359-65-5 5-decanoyl-2,2-dimethyl-1,3-dioxane-4,6-dione 
• 28254-78-6 (3R)-(-)-3-Hydroxydodecanoic acid 
• 18107-18-1 diazomethyl-trimethyl-silane 
• 143-07-7 lauric acid 

Relevant academic research and scientific papers

The Preparation of Optically Pure 3-Hydroxyalkanoic Acid. The Enantioface-differentiating Hydrogenation of the C=O Double Bond with Modified Raney Nickel. XXXVII

The enantioface-differentiating hydrogenation of methyl 3-oxoalkanoate (CH3(CH2)nCOCH2COOCH3, n=0, 6, 8, 10, 12) over the (R,R)-tartaric acid-NaBr-modified Raney nickel catalyst ((R,R)-TA-NaBr-MRNi) gave methyl (R)-3-hydroxyalkanoate (CH3(CH2)nCH(OH)CH2COOCH3, n=0, 6, 8, 10, 12) in an average optical yield of 85percent.After the methyl ester had been converted to dicyclohexylammonium salt of 3-hydroxyalkanoic acid, the salt was recrystallized three times from acetonitrile and then treated with acid to give optically pure (R)-3-hydroxyalkanoic acid (CH3(CH2)nCH(OH)CH2COOH, n=0, 6, 8, 10, 12) in a reasonable yield.From the hydrogenation product with (S,S)-TA-NaBr-MRNi, optically pure (S)-3-hydroxyalkanoic acid was obtained by the same process as above.

Enzymatic Regio- And Enantioselective C-H Oxyfunctionalization of Fatty Acids

Directed evolution of a P450 hydroxylase (P450BSβ) achieves an engineered enzyme that is able to catalyze C-H oxyfunctionalization of fatty acids (FAs) in a highly regio- and enantioselective fashion (>20:1 Cβ/Cα and > 99% ee in all cases). The biocatalyst displays high reactivity (TON up to 1540), takes inexpensive H2O2 as oxidant, and converts C11-C18 saturated FAs as well as naturally derived unsaturated oleic and linoleic acids to optically pure β-hydroxy FAs. Merging biocatalysis with chemical transformation, we further offer a chemoenzymatic strategy to access valuable FA derivatives bearing 1,3-diol, β-amino, β-lactone, and β-lactam functionalities in either enantiomeric form. Molecular docking studies provide a rationale for the regio- and enantioselectivity of this reaction.

Asymmetric synthesis of long chain β-hydroxy fatty acid methyl esters as new elastase inhibitors

Herein, β-hydroxy methyl esters with an even carbon chain length of 12-20 1b-5b were synthesized by three different asymmetric reduction methods I, II III from their corresponding β-keto methyl esters 1a-5a with the aim of determining their elastase activities. In method I, chiral catalyst A was prepared from chiral ligand (R)-binaphthol 1, while in method II, chiral catalyst B was synthesized from (2R,3R)-diisopropyl tartrate 2. Chiral catalyst B has not previously been used in asymmetric borane reductions or in the asymmetric synthesis of chiral β-hydroxy methyl esters. In method III, an asymmetric reduction was catalysed by (R)-Me-CBS oxazaborolidine 3. Hydride transfer was carried out in all of these methods by BH3· SMe2. Chiral hydroxy methyl esters with an (S)-configuration were synthesized by method I and with an (R)-configuration via methods II and III. The chiral hydroxy methyl esters obtained were analysed by chiral HPLC for their ee % values. Methods I, II and III were applied to long chain β-keto methyl esters for the first time. The reduction methods I, II and III were examined in terms of reaction yield and enantiomeric excess according to carbon chain length and the variable ratio of chiral catalysts to β-keto methyl ester. The highest enantiomeric excess of 90% ee was found in method III for 12 and 14 carbon numbers.

Over 98% optical yield achieved by a heterogeneous catalysis. Substrate design and analysis of enantio-differentiating factors of tartaric acid-modified Raney nickel hydrogenation

Tartaric acid-modified Raney nickel (TA-MRNi) is a chiral heterogeneous catalyst for the hydrogenation of prochiral ketones. An optical yield (OY) of 86% with methyl acetoacetate (1) as a substrate was improved to 94-96% by employing β-keto esters having a proper bulkiness at the γ-position. The γ-bulkiness effect contributes to a high intrinsic enantio-differentiating ability (factor-i) of the TA-MRNi catalysis. Through the study, we found the best substrate, γ-cyclopropyl-β-keto ester, the hydrogenation of which resulted in 98.6% OY. This further improvement in the OY was ascribed to a smaller contribution of non-enantio-differentiating hydrogenation (N-site catalysis) due to the substrate-specific activation of the enantio-differentiating hydrogenation by the chiral modifier. The OY of the hydrogenation of 1 was analyzed by comparing with well-behaved β-keto esters, and the contribution of the factor-i and the N-site to the OY value was evaluated to deduce the origin of the enantiodifferentiation.

Application of the Tethered Biginelli reaction for enantioselective synthesis of batzelladine alkaloids. Absolute configuration of the tricyclic guanidine portion of batzelladine B

Tethered Biginelli condensation of enantioenriched hexahydropyrrolopyrimidines 8 with β-ketoesters provides efficient asymmetric access to tricyclic guanidines 9 having a syn relationship of the angular C2a and C8a hydrogens. This reaction was employed to realize the first practical enantioselective access to this fragment of batzelladine alkaloids B (2) and E (5). The efficiency of this strategy is illustrated in the synthesis of the dextrorotatory enantiomer of batzelladine B methanolysis product 10 in 10 steps and 25% overall yield from 2-nonanone and methyl acetoacetate. The asymmetric synthesis of 1.0 establishes that the absolute configuration of the tricyclic portion of batzelladine B (2) is 25aR,28S,30R. The 4-methyl-7-alkyl-1,2,2a,3,4,5,6,7,8,8a-decahydro-5,6,8b- triazaacenaphthalene-3-carboxylic acid subunit, e.g., 29, of batzelladine alkaloids A (1), D (4), F (6), and G was also prepared for the first time by catalytic hydrogenation of tricyclic guanidines 26 having the 2a,8a-anti stereochemistry.

An Improved Asymmetrically-Modified Nickel Catalyst Prepared from Ultrasonicated Raney Nickel

The ultrasonic irradiation of Raney nickel catalyst in water followed by the removal of the resulting turbid supernatant gave an excellent nickel catalyst (RNi-U) which generated an asymmetrically-modified nickel catalyst.An EPMA (SEM-EDX) study indicated that RNi-U consisted of a fairly pure nickel surface of homogeneous size.Tartaric acid-NaBr-modified RNi-U (TA-NaBr-MRNi-U) showed a high enantio-differentiating ability as well as reactivity in the hydrogenation of prochiral ketones such as 1,3-diones and 3-oxoalkanoic acid esters.

Highly Efficient Enantio-differentiating Hydrogenation over an Ultrasonicated Raney Nickel Catalyst Modified with Tartaric Acid

A tartaric acid-NaBr-modified nickel catalyst prepared from ultrasonicated Raney nickel showed excellent enantio-differentiating and hydrogenating activity in the hydrogenation of a series of 3-oxoalkanoate and 1,3-diketones.