共查询到20条相似文献,搜索用时 15 毫秒
1.
Hyun Seung Lee 《Tetrahedron letters》2009,50(19):2274-9061
An expedient method was developed for the synthesis of 1,4,5,6-tetrahydropyridines by radical cyclization protocol involving consecutive 1,5-hydrogen transfer and double bond isomerization process starting from Baylis-Hillman adducts. 相似文献
2.
Saravanan Gowrisankar 《Tetrahedron letters》2008,49(43):6241-6244
We prepared various 1,5-dicarbonyl and related compounds from Baylis-Hillman adducts by using a Pd-mediated decarboxylative protonation protocol. 相似文献
3.
Eun Sun Kim 《Tetrahedron letters》2009,50(46):6286-1750
An efficient palladium-catalyzed two-step protocol for the synthesis of Baylis-Hillman adducts of acrylamide was developed. The method involved the preparation of Baylis-Hillman adducts of acrylonitrile and a Pd-catalyzed hydration of nitrile with acetaldoxime. 相似文献
4.
Hyun Seung Lee 《Tetrahedron letters》2009,50(47):6480-6483
The reaction of Baylis-Hillman acetates and ethyl mercaptoacetate in the presence of DBU in DMF produced 2,3,4-trisubstituted tetrahydrothiophenes at room temperature as a diastereomeric mixture via the sequential SN2′ and Michael addition. Aromatization of tetrahydrothiophenes by DDQ oxidation produced 2,3,4-trisubstituted thiophenes in good yields. 相似文献
5.
Ko Hoon Kim 《Tetrahedron letters》2009,50(38):5322-5609
We disclosed an efficient synthetic method of 2,4,5-trisubstituted 1,4-pentadienes from Baylis-Hillman adducts via the Pd-catalyzed decarboxylation-elimination protocol as the key step. 相似文献
6.
Syntheses of 2-amino-2,3-dihydrobenzofuran derivatives 3a-g and fully substituted furans 5a-f were achieved starting from the Baylis-Hillman adducts. We prepared 2-amino-2,3-dihydrobenzofurans from the Baylis-Hillman adducts of methyl and ethyl acrylates and fully substituted furans from the Baylis-Hillman adducts of alkyl vinyl ketones. 相似文献
7.
A palladium-mediated carbonylative cyclization reaction of Baylis-Hillman adducts is disclosed. This simple, efficient and straightforward sequence leads to the formation of an array of 3-alkenylphthalides with different substitution patterns on the aromatic ring, with good chemical yields and selectivities. 相似文献
8.
Serendipitous synthesis of 2-amino-2,3-dihydrobenzofuran derivatives 4a-g was achieved starting from the Baylis-Hillman adducts. In the reaction sequence, intramolecular oxygen atom transfer from nitrogen atom to arene moiety was observed. 相似文献
9.
Novel pentacyclic benzoazepino[2,1-a]isoindole derivatives were synthesized by palladium-mediated consecutive cyclization from enamides of Baylis-Hillman adducts. 相似文献
10.
Ko Hoon Kim 《Tetrahedron letters》2010,51(26):3368-40
A facile synthesis of benzofulvene derivatives was carried out starting from the Baylis-Hillman adducts of 2-bromobenzaldehyde via the sequential bromination, In-mediated Barbier reaction with aldehyde, acetylation, Pd-catalyzed intramolecular Heck reaction, and the elimination of AcOH. 相似文献
11.
An efficient and regioselective introduction method of 2-methylpyridines to the secondary position of Baylis-Hillman adducts has been developed. A base treatment of 2-methylpyridinium salt of Baylis-Hillman bromide generated N-allylenamine intermediate which underwent a facile 3-aza-Cope rearrangement under mild conditions to produce the product. 相似文献
12.
Mi Jung Lee 《Tetrahedron》2006,62(13):3128-3136
A new and regioselective [4+2] benzannulation protocol toward polysubstituted benzenes was developed. A nitroalkane derivative, which was prepared from Baylis-Hillman adduct, served as the four-carbon unit and a Michael acceptor as a two-carbon unit. Vinyltriphenylphosphonium salt could also be used as a Michael acceptor efficiently. 相似文献
13.
We have developed an efficient method for the synthesis of 2,5-dihydrofuran and 2,5-dihydropyrrole skeletons from the simply modified Baylis-Hillman adducts via RCM reaction. 相似文献
14.
Hyun Seung Lee 《Tetrahedron letters》2007,48(23):4119-4122
We synthesized poly-substituted pyrrole derivatives 4a-e, 7a-c and 10a-d from the reaction of phenacyl bromide and the aza-Baylis-Hillman adducts 1a-d or their rearranged derivatives 5a-e. The pyrroles were synthesized via the successive N-alkylation, Michael addition, elimination of p-toluenesulfinic acid and oxidative aromatization processes. 相似文献
15.
16.
Ka Young Lee 《Tetrahedron letters》2005,46(32):5387-5391
Facile synthetic method of 2H-indazole derivatives was developed involving DDQ oxidation of pyrazoles, which were prepared starting from the Baylis-Hillman adducts of 2-cyclohexen-1-one. 相似文献
17.
Seong Jin Kim 《Tetrahedron letters》2007,48(6):1069-1072
3,5,6-Trisubstituted α-pyrones were synthesized starting from the Baylis-Hillman adducts. The synthesis was carried out via the sequential introduction of ketone at the primary position of Baylis-Hillman adduct, lactonization, and the following oxidation with PCC. 相似文献
18.
Eun Sun Kim 《Tetrahedron letters》2009,50(36):5098-1390
An efficient synthetic protocol of fully substituted α-pyrones has been developed starting from the Baylis-Hillman adducts. Subsequent Diels-Alder reaction of the α-pyrones and DMAD produced poly-substituted aromatic compounds in high yields. 相似文献
19.
Seung Chan Kim 《Tetrahedron》2008,64(1):103-109
Poly-substituted benzenes were synthesized in moderate yields starting from the Baylis-Hillman adducts. The synthesis was carried out by two steps via first synthesis of cyclohexene intermediates and the following DBU-assisted unusual dehydrogenation. 相似文献
20.
Polysubstituted phenol derivatives were synthesized regioselectively starting from the Baylis-Hillman adducts via the formal [4+2] annulation protocol as the key step. 相似文献