38484-41-2Relevant academic research and scientific papers
Polycyclic bridgehead acetals with enol functionality: one-pot assembly from aliphatic ketones and acetylene in KOH/DMSO suspension
Schmidt, Elena Yu.,Bidusenko, Ivan A.,Cherimichkina, Natalia A.,Ushakov, Igor A.,Trofimov, Boris A.
, p. 4510 - 4517 (2016/07/07)
Aliphatic and cycloaliphatic ketones undergo selective multi-site cascade C–H functionalization with acetylene in the KOH/DMSO superbase suspension under mild conditions (70–80?°C, 0.5–1.0?h) to afford in one synthetic operation polycyclic bridgehead acet
Fluoride-assisted activation of calcium carbide: A simple method for the ethynylation of aldehydes and ketones
Hosseini, Abolfazl,Seidel, Daniel,Miska, Andreas,Schreiner, Peter R.
supporting information, p. 2808 - 2811 (2015/06/16)
The fluoride-assisted ethynylation of ketones and aldehydes is described using commercially available calcium carbide with typically 5 mol % of TBAF·3H2O as the catalyst in DMSO. Activation of calcium carbide by fluoride is thought to generate an acetylide "ate"-complex that readily adds to carbonyl groups. Aliphatic aldehydes and ketones generally provide high yields, whereas aromatic carbonyls afford propargylic alcohols with moderate to good yields. The use of calcium carbide as a safe acetylide ion source along with economic amounts of TBAF·3H2O make this procedure a cheap and operationally simple method for the preparation of propargylic alcohols.
Alkynylation of aldehydes and ketones using the Bu4NOH/H 2O/DMSO catalytic composition: A wide-scope methodology
Schmidt, Elena Yu.,Cherimichkina, Natalia A.,Bidusenko, Ivan A.,Protzuk, Nadezhda I.,Trofimov, Boris A.
, p. 4663 - 4670 (2014/08/05)
The Favorsky reaction of a wide range of aldehydes and ketones with alkynes has been implemented under mild conditions (5-20 C). Using a Bu 4NOH/H2O/DMSO catalytic system, propargylic alcohols are formed cleanly in 39-93% (mostly 72-93%) yields and with ca. 100% selectivity. The method is suitable for aliphatic, aromatic, and heteroaromatic aldehydes and ketones, and for aliphatic, aromatic, and functionalized acetylenes. Thus, this represents the most general and efficient protocol to achieve the Favorsky reaction. Copyright
Stoichiometric cyclotrimerisation of chiral alkynes at a ruthenium centre: Preparation of optically active (η6-arene)(η4-cycloocta-1,5-diene)ruthenium(0) complexes
Pertici, Paolo,Verrazzani, Alessandra,Pitzalis, Emanuela,Caporusso, Anna Maria,Vitulli, Giovanni
, p. 246 - 253 (2007/10/03)
The chiral alkynes (S)-MeCH(R)-C≡CH, 2 (R = Et, 3-methyl-1-pentyne, a; iPr, 3,4-dimethyl-1-pentyne, b; tBu, 3,4,4-trimethyl-1-pentyne, c), containing a stereogenic centre in α position to the triple bond, react at room temperature with the complex Ru(η6-naphthalene)(η4-COD), 1, to give the corresponding optically active complexes Ru{η6-(S)-1,3,5-C6H3[CH(Me)R] 3}(η4-COD), 6, and Ru{η6-(S)-1,2,4-C6H3[CH(Me)R] 3}(η4-COD), 7, the η6-1,3,5-arene regioisomer being the prevalent product. With (S)-2a, a mixture of 6a and 7a (6a/7a = 90:10) is obtained and, with the more sterically demanding alkynes (S)-2b and (S)-2c, the regioselectivity to the corresponding complexes 6b and 6c is almost complete. This synthetic procedure does not involve the stereogenic centres on the alkynes and it proceeds with complete stereoselectivity.
Permethylated β-Cyclodextrin as Chiral Solvating Agent for the NMR Assignment of the Absolute Configuration of Chiral Trisubstituted Allenes
Uccello-Barretta, Gloria,Balzano, Federica,Caporusso, Anna Maria,Iodice, Antonietta,Salvadori, Piero
, p. 2227 - 2231 (2007/10/02)
Permethylated β-cyclodextrin is a convenient chiral solvating agent (CSA) for the determination by NMR of the enantiomeric purities of chiral trisubstituted allenes and of their absolute configuration.All the allene proton resonance are deshielded, and this effect is stronger for the (S)-enantiomer of the allene than for the (R)-enantiomer.
REACTIONS OF NITROGEN NUCLEOPHILES WITH 1-BROMOALLENES: REGIOSELECTIVE SYNTHESIS OF PROPARGYLAMINES
Geri, Roberto,Polizzi, Carmela,Lardicci, Luciano,Caporusso, Anna Maria
, p. 241 - 248 (2007/10/02)
The results of a study on the reactivity of 3-alkyl- and 3,3-dialkyl-1-bromo-1,2-dienes 2 towards nitrogen nucleophiles, such as aqueous ammonia, lithium amide, aliphatic and aromatic amines allowed us to propose new methods for the synthesis of propargylamines, 1, with an available acetylenic hydrogen.The regio- and the stereoselectivity of these reactions are examined and possible mechanisms are discussed.
AN EFFICIENT AND QUICK LABORATORY SCALE METHOD FOR THE ETHYNYLATION OF SOME ALIPHATIC AND CYCLOALIPHATIC CARBONYL COMPOUNDS.
Verkruijsse, Hermann D.,Graaf, Wim de,Brandsma, Lambert
, p. 131 - 134 (2007/10/02)
A number of aliphatic and cycloaliphatic carbonyl compounds have been ethynylated in tetrahydrofuran at atmospheric pressure using uncomplexed potassium tert-butoxide as a catalyst.
The reaction of some propargyl alcohols with benzeneselenenyl chloride
Garratt, Dennis G.,Beaulieu, Pierre L.,Morisset, Veronique M.
, p. 927 - 934 (2007/10/02)
The reaction of benzeneselenenyl chloride with twenty-two propargyl alcohols in methylene chloride solution is reported.Products of both Markownikoff and anti-Markownikoff regiochemistry are formed in an anti stereospecific manner.The regioselectivity or specificity is found to be very dependent upon the nature of the substituents geminal to the alcoholic moiety.In general the presence of bulky substituents geminal to the alcoholic moiety tend to favour formation of the anti-Markownikoff adduct under conditions of kinetic control.The Markownikoff adducts are found to be favoured thermodynamically.
