7236-78-4Relevant academic research and scientific papers
Efficient Synthesis of γ-Lactones by Cobalt-Catalyzed Carbonylative Ring Expansion of Oxetanes under Syngas Atmosphere
Tang, Yitian,Shen, Chaoren,Yao, Qiyi,Tian, Xinxin,Wang, Bo,Dong, Kaiwu
, p. 5898 - 5902 (2020/10/02)
A practical route from oxetane or thietane to γ-(thio)butyrolactone via solvated-proton-assisted cobalt-catalyzed carbonylative ring expansion under syngas atmosphere has been established. A wide variety of γ-(thio)butyrolactones can be afforded in good to excellent yields. The versatility of this method has been well demonstrated in the synthesis of intermediates towards the natural product Arctigenin as well as the pharmaceuticals Baclofen and Montelukast. The observed promoting effect of glycol ether solvent has been rationally interpreted.
Synthesis method of butyrolactone compound
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Paragraph 0019-0054; 0055, (2020/07/21)
The invention relates to a synthesis method of a butyrolactone compound. The synthesis method comprises the following step: in the presence of a solvent and a cobalt catalyst, converting an oxetane compound shown as general formula I into a butyrolactone compound shown as general formula II through carbonyl insertion ring expansion reaction in an atmosphere of CO and H2. Compared with an existingmethod for synthesizing butyrolactone through oxetane carbonylation ring expansion reaction in a carbon monoxide atmosphere, the synthesis method of a butyrolactone compound provided by the inventionhas the advantages of excellent catalytic activity, excellent chemical selection, wide substrate applicability, mild reaction conditions and the like; compared with other methods for synthesizing butyrolactone compounds, the method provided by the invention has the advantages of wide substrate range, high atom economy, no need of noble metal catalysis and the like, therefore the method has a wideapplication prospect.
Synthesis of β,β-disubstituted γ-butyrolactones by chemo-selective oxidation of 1,4-diols and γ-hydroxy olefins with rucl3/NaIO4
Gao, Rong,Fan, Rong,Canney, Daniel J.
supporting information, p. 661 - 665 (2015/03/14)
Substituted γ-butyrolactones represent an important group of structural fragments commonly found in natural products, receptor ligands, and drug molecules. Interest in preparing a library of substituted γ-butyrolactones and finding that limited routes to β-substituted lactones exist, led to the development of an efficient approach for the synthesis of β,β-disubstituted γ-butyrolactones. Readily prepared substituted 1,4-diols and γ-hydroxy olefins were treated with the -RuCl3/NaIO4 oxidation system to provide the target β,β-disubstituted γ-butyrolactones in modest to good yields. The reaction goes through a lactol intermediate that was isolated and characterized for selected compounds. The approach supplies an efficient and versatile method for the synthesis of these important heterocyclic structures. Importantly, the present work is the first report that demonstrates the ability of RuCl3/NaIO4 to selectively oxidize primary hydroxyl groups in the presence of secondary alcohols to prepare lactones in good yields.
Spirolactones from Dirhodium(II)-Catalyzed Diazo Decomposition with Regioselective Carbon-Hydrogen Insertion
Doyle, Michael P.,Dyatkin, Alexey B.
, p. 3035 - 3038 (2007/10/02)
Dirhodium(II) caprolactamate, Rh2(cap)4, catalyzes diazo decomposition of cycloalkylmethyl diazoacetates which form spirolactones in moderate to high yield by insertion into a tertiary carbon-hydrogen bond.Similar results are obtained with diazoacetates derived from tetrahydropyran-2-methanol and tetrahydrofurfuryl alcohol but not from cyclopropylmethanol.With tetrahydrofuran-3-ylmethyl diazoacetate, Rh2(cap)4 catalysis promotes δ-lactone formation via insertion into the oxygen-activated secondary C-H bond instead of γ-lactone formation by carbene insertion into the unactivated tertiary C-H bond.However, when both 1,5- and 1,6-positions are activated for insertion by adjacent oxygen atoms, as in (2,2-dimethyl-1,3-dioxolan-4-yl)methyl diazoacetate, five-membered ring formation occurs exclusively in Rh2(cap)4-catalyzed reactions, whereas use of dirhodium(II) acetate leads to both insertion products.
Composes heterocycliques spiranniques. V. Synthese et etude configurationnelle dans la serie de l'oxa-2 spirodecane
Picard, Philippe,Moulines, Jean,Lecoustre, Max
, p. 65 - 70 (2007/10/02)
The 8-t-butyl-2-oxaspirodecan-3-one, 8-t-butyl-2-oxaspirodecane and its 3-methylated derivatives were synthesized by different routes starting from methyl 4-t-butylcyclohexanecarboxylate, 4-t-butylmethylenecyclohexane and methyl 4-t-butylcyclohexylidenecyanoacetate.The cis (-CH2O axial) and trans (-CH2O equatorial) isomers were isolated by preparative HPLC ; their configurations were established from (1) the known stereoselectivity of the reaction involved in the cis/trans ratio controlling step (2) their proton and 13C nmr spectra.
