58102-76-4Relevant academic research and scientific papers
Synthesis of Enantioenriched 3,4-Disubstituted Chromans through Lewis Base Catalyzed Carbosulfenylation
Denmark, Scott E.,Laverny, Aragorn,Menard, Travis
, p. 14290 - 14310 (2021/11/12)
A method for the catalytic, enantioselective, carbosulfenylation of alkenes to construct 3,4-disubstituted chromans is described. Alkene activation proceeds through the intermediacy of enantioenriched, configurationally stable thiiranium ions generated from catalytic, Lewis base activation of an electrophilic sulfenylating agent. The transformation affords difficult-to-generate, enantioenriched, 3,4-disubstituted chromans in moderate to high yields and excellent enantioselectivities. A variety of substituents are compatible including electronically diverse functional groups as well as several functional handles such as aryl halides, esters, anilines, and phenols. The resulting thioether moiety is amenable to a number of functional group manipulations and transformations. Notably, the pendant sulfide was successfully cleaved to furnish a free thiol which readily provides access to most sulfur-containing functional groups which are present in natural products and pharmaceuticals.
Copper(I)-catalyzed highly regio- and stereoselective hydrosilylation of terminal alkynes with boryldisiloxane
Zhou, Hui,Wang, Yan-Bo
, p. 2512 - 2516 (2015/04/14)
By employing 1,1,3,3-tetramethyl-1,3-(pinacolboryl)disiloxane as a novel silicon source, the N-heterocyclic carbene copper complex catalyzed hydrosilylation of terminal alkynes was developed to prepare vinyldisiloxanes in a highly regio- and stereoselective manner. A number of functional groups, including ether, ester, cyano, nitro, halo, hydroxyl, cyclopropyl, and aryl groups, were tolerated under the optimized conditions. A mechanistic investigation was undertaken by using density functional theory calculations. This approach allows facile entry to unsymmetrical disubstituted (E)-alkenes by Pd-catalyzed cross-coupling reactions.
From precursor to catalyst: The involvement of [Ru(η5-Cp?)Cl2]2 in highly branch selective allylic etherification of cinnamyl chlorides
Siddappa, Ravi Kumara Guralamatta,Chang, Chih-Wei,Chein, Rong-Jie
supporting information, p. 1031 - 1035 (2015/02/19)
(RuCp?Cl2)2, a general entry into Cp?Ru sandwich and half-sandwich chemistry was first used as a precatalyst in allylic etherification of cinnamyl chlorides with up to 98:2 regioselectivity (19 examples). Both the solvent effect and the exsiccant reaction condition are crucial to the reactivity and selectivity. Preliminary mechanism studies and the demonstration of Fluoxetine synthesis were presented in this work as well.
An efficient palladium-catalyzed synthesis of cinnamyl ethers from aromatic halides, phenols, and allylic chloride
Wang, Wei,Zhou, Rong,Jiang, Zhi-Jie,Wang, Kun,Fu, Hai-Yan,Zheng, Xue-Li,Chen, Hua,Li, Rui-Xiang
, p. 616 - 622 (2014/05/20)
A one-pot, two-step catalytic protocol for the preparation of cinnamyl ethers from simple and readily available aryl halides, phenols and allyl chloride is reported for the first time. This simple and highly efficient palladium nanoparticles catalytic system shows good regio- and stereoselectivities and affords the desired products in good to high yields (49-85%) from aryl iodides. Furthermore, less reactive aryl bromides can also give the cinnamyl ethers in moderate yields (24-72%).
Catalytic enantioselective aziridoarylation of aryl cinnamyl ethers toward synthesis of trans-3-amino-4-arylchromans
Hajra, Saumen,Sinha, Debarshi
body text, p. 7334 - 7340 (2011/11/06)
Catalytic enantioselective one-pot aziridoarylation reaction of aryl cinnamyl ethers has been demonstrated in detail. Combination of suitable copper catalyst and chiral bis-oxazoline ligand was found to be very efficient for asymmetric aziridination followed by intramolecular arylation (Friedel-Crafts) reaction to provide a general and direct method for the synthesis of trans-3-amino-4-arylchromans with high regio-, diastereo- (dr > 99:1), and enantioselectivity (up to 95% ee) with moderate yield. trans-3-Amino-4- arylchroman is an advanced intermediate for the synthesis of chromenoisoquinoline compounds such as doxanthrine, a potent and selective full agonist for the dopamine-D1 receptor.
(Cyclopentadienyl)ruthenium-catalyzed regio- and enantioselective decarboxylative allylic etherification of allyl aryl and alkyl carbonates
Austeri, Martina,Linder, David,Lacour, Jerome
experimental part, p. 3339 - 3347 (2011/02/23)
(Cyclopentadienyl)tris(acetonitrile)ruthenium hexafluorophosphate {[CpRu(NCMe)3][PF6] or (cyclopentadienyl) (I·6-naphthalene)ruthenium hexafluorophosphate {[CpRu(I·6-naphthalene)][PF6]} in combination with a pyridine oxazoline ligand efficiently catalyze the decarboxylative allylic rearrangement of allyl aryl carbonates. Good levels of regio- and enantioselectivity are obtained. Starting from enantioenriched secondary carbonates, the reaction is stereospecific and the corresponding allylic ethers are obtained with net retention of configuration. An intermolecular version of this transformation was also developed using allyl alkyl carbonates as substrates. Conditions were found to obtain the corresponding products with similar selectivity as in the intramolecular process. Through the use of a hemi-labile hexacoordinated phosphate counterion, a zwitterionic air- and moisture-stable chiral ruthenium complex was synthesized and used in the enantioselective etherification reactions. This highly lipophilic metal complex can be recovered and efficiently reused in subsequent catalysis runs. Copyright
Regio- and enantioselective O-allylation of phenol and alcohol catalyzed by a planar-chiral cyclopentadienyl ruthenium complex
Onitsuka, Kiyotaka,Okuda, Haruki,Sasai, Hiroaki
, p. 1454 - 1457 (2008/12/22)
(Chemical Equation Presented) Design of an asymmetric catalyst: The planar-chiral cyclopentadienyl ruthenium complex shown in the scheme effectively catalyzes the reactions of unsymmetrically substituted allyl halides with phenol and alcohol to give the corresponding branched allyl ethers with high regio- and enantioselectivity.
