Multifunctional chiral phosphines-catalyzed highly diastereoselective and enantioselective substitution of Morita–Baylis–Hillman adducts with oxazolones
作者:Yuan-Liang Yang、Cheng-Kui Pei、Min Shi
DOI:10.1039/c1ob00017a
日期:——
Multifunctional chiral phosphine (phosphine–thiourea type) L2-catalyzed allylicsubstitutions of MBH adducts 1 with oxazolones 2 produce the corresponding optically active adducts 3 in good to excellent yields and ee's as well as moderate to good de's under mild conditions. The synergistic interaction between hydrogen bond donor site and nucleophilic site has been discussed, indicating that finely
Novel Quinidine-Derived Organocatalysts for the Asymmetric Substitutions of O-Boc-Protected Morita-Baylis-Hillman Adducts
作者:Cheng-Kui Pei、Xiu-Chun Zhang、Min Shi
DOI:10.1002/ejoc.201100501
日期:2011.8
A series of novelquinidine-derivedorganocatalysts was synthesized and utilized for the asymmetricsubstitution of O-Boc-protectedMorita–Baylis–Hillmanadducts with various carbamates and tosylcarbamates, affording the corresponding products in good to high yields (up to 91 % yield) with moderate to high ee values (up to 96 % ee) under mild conditions.
Brucine N-oxide-catalyzed Morita–Baylis–Hillman reaction of vinyl ketones: a mechanistic implication of dual catalyst system with proline
作者:Kyungsoo Oh、Jian-Yuan Li、Jinhyang Ryu
DOI:10.1039/c003667f
日期:——
The brucine N-oxide promoted Morita–Baylis–Hillman (MBH) reaction of vinyl ketones with aldehydes has been achieved. The corresponding asymmetric version of MBH reaction was also investigated, and the electron-deficient aryl aldehydes have emerged as suitable reaction partners for vinyl ketones; where proline was employed as a co-catalyst. In this dual catalyst system, proline is believed to form iminium
A convenient synthesis of 1,5-diarylpyrazoles from Baylis-Hillman adducts using HY-zeolite
作者:Mohammad Nikpassand、Manouchehr Mamaghani、Mohammad Ali Zanjanchi、Nosrat Olah Mahmoodi、Massomeh Mirzaeinejad
DOI:10.1016/j.cclet.2009.07.020
日期:2010.1
A facile and convenient protocol was developed for the synthesis of 1,5-diarylpyrazoles using Baylis-Hillman adducts in the presence of HY-zeolite as an efficient recyclable heterogeneous catalyst in reasonable reaction times (1.5-2.5 h) and high yields (78-90%). (C) 2009 Manouchehr Mamaghani. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
Facile synthesis of biarylmethanes and tetrasubstituted arenes <i>via</i> a base-mediated [3 + 3] benzannulation reaction of Morita–Baylis–Hillman adducts and unsaturated sulfones
作者:Deepak Yadav、Sunil K. Sharma、Rajeev S. Menon
DOI:10.1039/c9ob00214f
日期:——
A facile DBU-mediated [3 + 3] benzannulation reaction of 1,3-bis-sulfonyl propenes and Morita–Baylis–Hillman (MBH) bromides is described. The benzannulation reaction afforded bis-sulfonyl biarylmethanes/arenes with complete regioselectivity. The products may be converted readily into corresponding benzophenones via site-selective benzylic oxidation.