5635-42-7Relevant articles and documents
Searching for New Polymorphs by Epitaxial Growth
Simbrunner, Josef,Schrode, Benedikt,Hofer, Sebastian,Domke, Jari,Fritz, Torsten,Forker, Roman,Resel, Roland
, p. 568 - 578 (2021/01/14)
The formation of unknown polymorphs due to the crystallization at a substrate surface is frequently observed. This phenomenon is much less studied for epitaxially grown molecular crystals since the unambiguous proof of a new polymorph is a challenging tas
Total synthesis of Cinncassin A1
Nuriye, Ahmed Y.,Craescu, Cristina V.
, p. 2640 - 2648 (2020/04/15)
In this communication, we report the first total synthesis of the phenolic natural product Cinncassin A1, which was recently isolated from the twigs of the cinnamon plant (Cinnamomum cassia). The novel and concise synthesis strategy involves a highly diastereoselective titanium enolate homocoupling and a permanganate-mediated oxidative lactonization reaction as key steps. The structure of the compound was verified by single-crystal X-ray crystallography.
Asymmetric Synthesis of γ-Lactones through Koga Amine-Controlled Addition of Enediolates to α,β-Unsaturated Sulfoxonium Salts
Peraino, Nicholas J.,Kaster, Sven H.,Wheeler, Kraig A.,Kerrigan, Nessan J.
, p. 606 - 615 (2017/04/26)
A chiral Koga amine-controlled asymmetric synthesis of cis-γ-lactones through a formal [3 + 2] cycloaddition of enediolates with α,β-unsaturated sulfoxonium salts is described. The desired structural motif was formed in moderate to good yields (50-71% for 13 examples), with good to very good diastereoselectivity (dr 5:1 to 10:1 for 20 examples), favoring the cis-isomer, and good to excellent enantioselectivity (70-91% ee for 13 examples).
Diastereoselective synthesis of γ-lactones through reaction of enediolates with α,β-unsaturated sulfoxonium salts
Peraino, Nicholas J.,Wheeler, Kraig A.,Kerrigan, Nessan J.
supporting information, p. 1735 - 1737 (2015/04/14)
Studies of the reaction of lithium enediolates with α,β-unsaturated sulfoxonium salts are described. γ-Lactones were formed in very good to excellent yields (82% → 99% for 11 examples) and with very good to excellent diastereoselectivity (dr >90:10 for 10
Unusual regioselectivity in the opening of epoxides by carboxylic acid enediolates
Domingo, Luis R.,Gil, Salvador,Parra, Margarita,Segura, Jose
, p. 1303 - 1311 (2008/12/20)
Addition of carboxylic acid dianions appears to be a potential alternative to the use of aluminium enolates for nucleophilic ring opening of epoxides. These conditions require the use of a sub-stoichiometric amount of amine (10% mol) for dianion generation and the previous activation of the epoxide with LiCl. Yields are good, with high regioselectivity, but the use of styrene oxide led, unexpectedly, to a mixture resulting from the attack on both the primary and secondary carbon atoms. Generally, a low diastereoselectivity is seen on attack at the primary center, however only one diastereoisomer was obtained from attack to the secondary carbon of the styrene oxide.
Ruthenium(salen)-catalyzed aerobic oxidative desymmetrizatin of meso-diols and its kinetics
Shimizu, Hideki,Onitsuka, Satoaki,Egami, Hiromichi,Katsuki, Tsutomu
, p. 5396 - 5413 (2007/10/03)
Chiral (nitrosyl)ruthenium(salen) complexes were found to be efficient catalysts for aerobic oxidative desymmetrization of meso-diols under photoirradiation to give optically active tactols. The scope of the applicability of this reaction ranges widely from acyclic diols to mono-cyclic diols, although fine ligand-tuning of the ruthenium(salen) complexes was required to attain high enantioselectivity (up to 93% ee). In particular, the nature of the apical ligand was found to affect not only enantioselectivity but also kinetics of the desymmetrization reaction. Spectroscopic analysis of the oxidation disclosed that irradiation of visible light is indispensable not only for dissociation of the nitrosyl ligand but also for single electron transfer from the alcohol-bound ruthenium ion to dioxygen.
The First Stereoselective Palladium-Catalyzed Cyclocarbonylation of β,γ-Substituted Allylic Alcohols
Brunner, Melanie,Alper, Howard
, p. 7565 - 7568 (2007/10/03)
β,γ-Substituted allylic alcohols react with CO in the presence of catalytic quantities of palladium acetate and 1,4-bis(diphenylphosphino)butane affording α,β-substituted-γ-butyrolactones in 42-85% isolated yields. The complete stereoselectivity observed