109-29-5Relevant academic research and scientific papers
A Simple Synthesis of trans-Δ9-Isoambrettolide, Dihydroambrettolide, and Methyl 16-Acetoxy-9-hexadecenoate
Villemin, Didier
, p. 154 - 155 (1987)
Δ9-Isoambrettolide (2) and methyl 16-acetoxy-9-hexadecenoate (3) are prepared from aleuritic acid and dimethylformamide dialkyl acetals by a one-pot reaction.Catalytic hydrogenation of products 2 and 3 affords dihydroambrettolide (6) and methyl 16-acetoxyhexadecanoate (7), respectively.
Lactonization of ω-Hydroxy Esters over Hydrous Zirconium(IV) Oxide
Kuno, Hideyuki,Shibagaki, Makoto,Takahashi, Kyoko,Honda, Ichiro,Matsushita, Hajime
, p. 571 - 574 (1992)
The lactonization of ω-hydroxy esters was carried out by catalysis with hydrous zirconium(IV) oxide.In the flow reaction system, ω-hydroxy esters were efficiently converted to give the corresponding lactones.In particular, it is noteworthy that heptanolide is obtained in good yield.In addition, it is possible to produce a large quantity of lactones in this catalyst system.
MACROCYCLIC LACTONES VIA BIOCATALYSIS IN NON-AQUEOUS MEDIA
Zhi-wei, Guo,Ngooi, T. K.,Scilimati, A.,Fuelling, Gerd,Sih, Charles J.
, p. 5583 - 5586 (1988)
The enantiospecificity of lipase-catalyzed lactonization of chiral (w-1)-hydroxy acids to form diolides in non-aqueous medium was investigated.
Effect of micelles on cyclization reactions: The use of N-hexadecyl-2- chloropyridinium iodide as an amphiphilic carboxyl-activating agent in lactonization and lactamization
Rico,Halvorsen,Dubrule,Lattes
, p. 415 - 420 (1994)
Lactonization and lactamization with a novel carboxyl-activating agent, N- hexadecyl-2-chloropyridinium iodide (C16PyCl,I), were investigated. The organization of this agent in micelles in the reaction medium facilitates cyclization giving rise to a micellar effect. Under these conditions, the corresponding lactam is produced from the ω-amino acid 12-aminododecanoic acid in good yield (double that obtained with the Mukaiyama reagent, N- methyl-2-chloropyridinium iodide C1PyCl,I). On the other hand, the yield of lactone from 16-hydroxyhexadecanoic acid was the same with either carboxyl- activating agent. These results were accounted for in terms of substrate- dependent micellar effects. Because of solubility effects, the ω-amino acids and ω-hydroxy acids are not localized in comparable ways vis a vis the interface and, thus, have different reactivities. Moreover, hydrolysis of the reagents, C16PyCl,I and C1PyCl,I, was also detected. The interference of this reaction with the cyclization process was also found to depend on a micellar effect with C16PyCl,I that is not observed with C1PyCl,I.
DMEAD: a new dialkyl azodicarboxylate for the Mitsunobu reaction
Hagiya, Kazutake,Muramoto, Natsuko,Misaki, Tomonori,Sugimura, Takashi
, p. 6109 - 6114 (2009)
Di-2-methoxyethyl azodicarboxylate (DMEAD) is prepared in 65% yield in two steps as a crystalline solid. Use of DMEAD in the Mitsunobu reaction of a variety of alcohols with pronucleophiles results in good yields of the products under sufficient stereospecificity of inversion, as conventional diisopropyl azodicarboxylate (DIAD) does. Isolation of the product is, however, much easier with DMEAD than that with DIAD, because the hydrazine produced from DMEAD is highly hydrophilic and is completely separable by a simple extraction into neutral water. Purification of the organic layer, after separation of the other by-product, triphenylphosphane oxide, by filtration, easily provides high purity of the product in a good yield. Concentration of the water layer yields the hydrazine, which can be reused for the preparation of DMEAD. One-step removal of the two by-products by the aqueous extraction was also possible when trimethylphosphane and DMEAD were employed.
Macrolactonization Reactions Driven by a Pentafluorobenzoyl Group**
Ciofini, Ilaria,Force, Guillaume,Leb?uf, David,Mayer, Robert J.,Perfetto, Anna
supporting information, p. 19843 - 19851 (2021/08/13)
Macrolactones constitute a privileged class of natural and synthetic products with a broad range of applications in the fine chemicals and pharmaceutical industry. Despite all the progress made towards their synthesis, notably from seco-acids, a macrolactonization promoter system that is effective, selective, flexible, readily available, and, insofar as possible, compatible with manifold functional groups is still lacking. Herein, we describe a strategy that relies on the formation of a mixed anhydride incorporating a pentafluorophenyl group which, due to its high electronic activation enables a convenient access to macrolactones, macrodiolides and esters with a broad versatility. Kinetic studies and DFT computations were performed to rationalize the reactivity of the pentafluorophenyl group in macrolactonization reactions.
Flow Chemistry under Extreme Conditions: Synthesis of Macrocycles with Musklike Olfactoric Properties
Seemann, Alexandra,Panten, Johannes,Kirschning, Andreas
supporting information, p. 13924 - 13933 (2021/05/29)
Starting from small cyclic ketones, continuous flow synthesis is used to produce medium-sized rings and macrocycles that are relevant for the fragrance industry. Triperoxides are important intermediates in this process and are pyrolyzed at temperatures above 250 °C. The synthesis is carried out in two continuously operated flow reactors connected by a membrane-operated separator. The practicality of flow chemistry is impressively demonstrated in this work by the use of hazardous reagent mixtures (30% H2O2, 65% HNO3) and the pyrolysis of no less problematic peroxides. All new macrocycles were tested for their olfactory properties in relation to musk.
Highly selective macrocyclic ring-closing metathesis of terminal olefins in non-chlorinated solvents at low dilution
Dumas, Adrien,Colombel-Rouen, Sophie,Curbet, Idriss,Forcher, Gwénael,Tripoteau, Fabien,Caijo, Frédéric,Queval, Pierre,Rouen, Mathieu,Baslé, Olivier,Mauduit, Marc
, p. 436 - 443 (2019/01/28)
A set of new ruthenium-indenylidene complexes bearing two unsymmetrical unsaturated N-cycloalkyl-NHC ligands were synthesized. These catalysts proved to be highly selective in the macrocyclic ring-closing metathesis performed in non-chlorinated solvents at low dilution (0.01 M). Without the requirement of benzoquinone derivatives to prevent the isomerisation side reactions, this environmentally friendly catalytic process promoted the synthesis of macrocyclic odorant molecules with remarkable >99% purity.
A General Catalytic Method for Highly Cost- and Atom-Efficient Nucleophilic Substitutions
Huy, Peter H.,Filbrich, Isabel
supporting information, p. 7410 - 7416 (2018/04/30)
A general formamide-catalyzed protocol for the efficient transformation of alcohols into alkyl chlorides, which is promoted by substoichiometric amounts (down to 34 mol %) of inexpensive trichlorotriazine (TCT), is introduced. This is the first example of a TCT-mediated dihydroxychlorination of an OH-containing substrate (e.g., alcohols and carboxylic acids) in which all three chlorine atoms of TCT are transferred to the starting material. The consequently enhanced atom economy facilitates a significantly improved waste balance (E-factors down to 4), cost efficiency, and scalability (>50 g). Furthermore, the current procedure is distinguished by high levels of functional-group compatibility and stereoselectivity, as only weakly acidic cyanuric acid is released as exclusive byproduct. Finally, a one-pot protocol for the preparation of amines, azides, ethers, and sulfides enabled the synthesis of the drug rivastigmine with twofold SN2 inversion, which demonstrates the high practical value of the presented method.
Polycyclic ketone monooxygenase from the thermophilic fungus Thermothelomyces thermophila: A structurally distinct biocatalyst for bulky substrates
Fürst, Maximilian J.L.J.,Savino, Simone,Dudek, Hanna M.,Castellanos, J. Rúben Gómez,De Souza, Cora Gutiérrez,Rovida, Stefano,Fraaije, Marco W.,Mattevi, Andrea
supporting information, p. 627 - 630 (2017/05/15)
Regio- and stereoselective Baeyer-Villiger oxidations are difficult to achieve by classical chemical means, particularly when large, functionalized molecules are to be converted. Biocatalysis using flavin-containing Baeyer-Villiger monooxygenases (BVMOs) is a wellestablished tool to address these challenges, but known BVMOs have shortcomings in either stability or substrate selectivity. We characterized a novel BVMO from the thermophilic fungus Thermothelomyces thermophila, determined its three-dimensional structure, and demonstrated its use as a promising biocatalyst. This fungal enzyme displays excellent enantioselectivity, acts on various ketones, and is particularly active on polycyclic molecules. Most notably we observed that the enzyme can perform oxidations on both the A and D ring when converting steroids. These functional properties can be linked to unique structural features, which identify enzymes acting on bulky substrates as a distinct subgroup of the BVMO class.
