59078-31-8Relevant academic research and scientific papers
Synthesis of 2-Alkynoates by Palladium(II)-Catalyzed Oxidative Carbonylation of Terminal Alkynes and Alcohols
Cao, Qun,Hughes, N. Louise,Muldoon, Mark J.
supporting information, p. 11982 - 11985 (2016/08/16)
A homogeneous PdIIcatalyst, utilizing a simple and inexpensive amine ligand (TMEDA), allows 2-alkynoates to be prepared in high yields by an oxidative carbonylation of terminal alkynes and alcohols. The catalyst system overcomes many of the limitations of previous palladium carbonylation catalysts. It has an increased substrate scope, avoids large excesses of alcohol substrate and uses a desirable solvent. The catalyst employs oxygen as the terminal oxidant and can be operated under safer gas mixtures.
Highly stereoselective generation of complex oxy -bicyclic scaffolds via an atom-economic Pd(II)-catalyzed hydroalkynylation, isomerization and diels-alder cycloaddition sequence
Shen, Ruwei,Chen, Ke,Deng, Qiulin,Yang, Jianjun,Zhang, Lixiong
supporting information, p. 1208 - 1211 (2014/03/21)
An atom-economic tandem Pd(II)-catalyzed hydroalkynylation, alkyne-allene isomerization, and Diels-Alder cycloaddition is reported. The reaction employs readily available starting substrates, proceeds in a highly ordered fashion, features high regio- and
Helical Disubstituted Polyacetylenes: Synthesis and Chiroptical Properties of Poly(phenylpropiolate)s
Lam, Jacky W.Y.,Dong, Yuping,Cheuk, Kevin K.L.,Tang, Ben Zhong
, p. 7927 - 7938 (2007/10/03)
Disubstituted polyacetylenes with helical chirality have been rarely prepared due to the involved synthetic difficulty, and we here report a facile polymerization system for the synthesis of such polymers. Two groups of chiral acetylenes, i.e., C6H5C≡CCO2R* {R* = [(1S)-endo]-(-)-borneyl (1), (1R,2S,5R)-(-)-menthyl (5), cholesteryl (6)} and C6H5C≡CCO2C 6H4CO2R* [R* = borneyl (2), menthyl (3), cholesteryl (4)], are prepared by esterifications of phenylpropiolic acids with borneol, menthol, and cholesterol. Polymerizations of 1-4 are effected by WCl6-Ph4Sn, giving poly(phenylpropiolate)s P1-P4 with high molecular weights in moderate yields. The structures and properties of the polymers are characterized and evaluated by IR, UV, NMR, CD, TGA, and SEM analyses. All the polymers are stable: neither decreases in their molecular weights nor changes in their spectra are detected after the polymers have been stored on shelf for ～3 years, and no weight losses are recorded when the polymers are heated to ～300 °C. Although the polymers do not possess regioregular Z or conformations, the polyacetylene backbones are induced to helically rotate by the chiral pendants, as verified by the strong Cotton effects in the backbone absorption region of the polymers (molar ellipticity up to 102 300 deg cm2 dmol-1). The polymers exhibit helical thermochromism, with their chain helicity being continuously and reversibly tunable by temperature change. The helical polymers are capable of self-assembling, as demonstrated by the formation of twisted ribbons upon diffusing a THF solution of P3 into hexane.
Diastereoselectivity in the intermolecular Pauson-Khand reaction of chiral 2-alkynoates
Fonquerna, Silvia,Moyano, Albert,Pericas, Miquel A.,Riera, Antoni
, p. 4239 - 4254 (2007/10/02)
Chiral 2-alkynoates have been readily prepared by condensation of several cyclohexyl- or camphor-based alcohols with 2-alkynoic acids or the corresponding acid chlorides. The hexacarbonyldicobalt complexes obtained therefrom reacted with olefins to afford the corresponding Pauson-Khand cyclopentenone adducts in good yields, with high regioselectivity, and with variable degrees of diastereoselectivity. In some instances, the degree of stereocontrol is superior to that observed for alkoxyacetylenes, so that the viability of an enantioselective approach to the intermolecular Pauson-Khand reaction of electron-deficient alkynes is demonstrated for the first time.
