41732-91-6Relevant academic research and scientific papers
O-H hydrogen bonding promotes H-atom transfer from α C-H bonds for C-alkylation of alcohols
Jeffrey, Jenna L.,Terrett, Jack A.,MacMillant, David W.C.
, p. 1532 - 1536 (2015/10/05)
The efficiency and selectivity of hydrogen atom transfer from organic molecules are often difficult to control in the presence of multiple potential hydrogen atom donors and acceptors. Here, we describe the mechanistic evaluation of a mode of catalytic activation that accomplishes the highly selective photoredox a-alkylation/lactonization of alcohols with methyl acrylate via a hydrogen atom transfer mechanism. Our studies indicate a particular role of tetra-n-butylammonium phosphate in enhancing the selectivity for α C-H bonds in alcohols in the presence of allylic, benzylic, α-C=O, and α-ether C-H bonds.
A new synthesis of γ-butyrolactones via AuCl3- or Hg(II)-catalyzed intramolecular hydroalkoxylation of 4-bromo-3-yn-1-ols
Reddy, Maddi Sridhar,Kumar, Yalla Kiran,Thirupathi, Nuligonda
, p. 824 - 827 (2012/04/05)
An efficient conversion of 4-bromo-3-yn-1-ols to γ-butyrolactones via AuCl3-catalyzed electrophilic cyclization (hydroxyl-assisted regioselective hydration) in wet toluene is described. Various secondary and tertiary alcohols including benzylic systems were found to be equally reactive with moderate to excellent yields obtained in all cases.
Improved synthesis of γ-lactones from cyclopropyl cyanoesters
Patel, Nandini C.,Schwarz, Jacob B.,Islam, Khondaker,Miller, Whitney,Tran, Tuan P.,Wei, Yunjing
experimental part, p. 2209 - 2215 (2011/07/07)
Cyclopropyl cyanoesters 2 were reliably converted to c-lactones 4 on treatment with aqueous sulfuric acid. The cyanoesters could be easily prepared from ketones or aldehydes in two steps, making this process particularly attractive from an efficiency standpoint. Copyright
A novel synthesis of γ,δ-unsaturated aldehydes from α-formyl-γ-lactones
Snowden, Roger L.,Brauchli, Robert,Linder, Simon
body text, p. 1216 - 1225 (2011/09/16)
A preparatively useful one-step transformation of γ,γ- disubstituted α-formyl-γ-lactones into trisubstituted γ,δ-unsaturated aldehydes is described, by means of catalytic amounts of either AcOH or AcOEt in the vapor phase over a glass support. A mechanistic rationale is proposed. Copyright
Synthesis of new furan derivatives and 4-hydroxy aldehydes from 4-hydroxy 1-enol ethers
Hoelemann, Alexandra,Reissig, Hans-Ulrich
, p. 1963 - 1970 (2007/10/03)
Starting from 4-hydroxy 1-enol ethers 3 different γ-lactols 4 were successfully prepared by acidic hydrolysis. Subsequent oxidation of 4 with pyridinium chlorochromate (PCC) led to γ-lactones 6 in good to excellent overall yields. Treatment of γ-lactols 4
A new coupling reaction between β-lactones and electrophiles mediated by a SmI2/(NiI2 catalytic) system
Machrouhi, Fouzia,Namy, Jean-Louis
, p. 11111 - 11122 (2007/10/03)
β-lactones react with ketones aldehydes and imines in the presence of a SmI2/(NiI2 catalytic) system to afford substituted tetrahydrofuranones and pyrrolidinones.
Spiro γ-lactones via aluminum enolate-spiroepoxide openings
Taylor, Stephen K.,Chmiel, Nikolas H.,Mann, Emily E.,Silver, Michael E.,Vyvyan, James R.
, p. 1009 - 1014 (2007/10/03)
The opening of several spiroepoxides by aluminum ester enolates is described. The isolated γ-hydroxy esters are cyclized to the corresponding spirolactones with high efficiency. Alternatively, the crude product from epoxide opening may be directly converted to the spirolactone without purification of the intermediate hydroxy ester. This methodology provides another complementary route to 1-oxaspiro[4.n]-2-one systems that are of structural and biological interest.
Synthesis and Applications of Tetrahydrofuran-Stable Substituted (3-Lithioxyalkyl)- and (4-Lithioxyalkyl)lithiums, Modified with Magnesium 2-Ethoxyethoxide
Kostas, Ioannis D.,Screttas, Constantinos G.
, p. 5575 - 5577 (2007/10/03)
Substituted hydroxyalkyl phenyl sulfides 3 have been synthesized from the corresponding allylic or homoallylic alcohols 2. Regiospecific cleavage of the C - SPh bond of the sulfides 3 by lithium dispersion in tetrahydrofuran (THF) led to the synthesis of substituted (3-lithioxyalkyl)- and (4-lithioxyalkyl)lithiums 4, most of which share the ω carbon with a carbocyclic ring. The organolithiums were modified with magnesium 2-ethoxyethoxide in order to suppress their reactivity toward THF cleavage, thus offering the advantage of preparing storable ethereal solutions of certain types of (lithioxyalkyl)lithiums. This strategy appears to be of rather broad scope. The functionalized organolithiums prepared in this way react normally with electrophilic reagents with yields in the range 35-55%. Thus, carboxylations of 4 yielded lactones 5, some of which are natural products, while reactions of 4 with benzophenone and cyclic ketones yielded 1,4- and 1,5-diols 6 and 7, respectively.
A new synthesis of lactones from tertiary alkenylcarbinols by cobalt-catalyzed photocarbonylation under ambient conditions
Chow, Yuan L.,Huang, Yu-Jin,Dragojlovic, Veljko
, p. 740 - 742 (2007/10/02)
In the presence of a Co catalyst, tertiary vinyl-, propenyl-, and allylcarbinols were chelatively cycloadded to carbon monoxide to produce lactones by xanthone-sensitized photoreaction in tetrahydrofuran, under CO at 1 atmosphere and at room temperature.At lower temperatures the isomerization of alkenyl-carbinols was suppressed and lactones were obtained with improved selectivity.The photoprocess was facilitated by addition of pyridine or hydrogen and retarded in presence of amines or phosphines.Mechanistic interpretations for the process and the accompanying effects are discussed.Key words: chelative carbonylation, photocarbonylation, carbonylation of olefins, lactones synthesis from alkenylalcohols.
Transition Metal Promoted Acetylene Isomerisation Reactions In Organic Synthesis
Quayle, Peter,Rahman, Shopna,Ward, E. Lucy M.,Herbert, John
, p. 3801 - 3804 (2007/10/02)
A transition metal mediated acetylene-vinylidene rearrangement has been developed for the synthesis of spirocyclic lactones
