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The first Pd-catalyzed Buchwald-Hartwig aminations at C-2 or C-4 in the estrone series.

ABSTRACT: A facile Pd-catalyzed C(sp²)-N coupling to provide a range of 2- or 4-[(subst.)phenyl]amino-13?-estrone derivatives has been achieved under microwave irradiation. The reactions were mediated with the use of Pd(OAc)₂ as a catalyst and KOt-Bu as a base in the presence of X-Phos as a ligand. The desired products have been obtained in good to excellent yields. The nature and the position of the aniline substituent at the aromatic ring influenced the outcome of the couplings. 2-Amino-13?-estrone was also synthesized in a two-step protocol including an amination of 2-bromo-13?-estrone 3-benzyl ether with benzophenone imine and subsequent hydrogenolysis.

SUBMITTER: Bacsa I

PROVIDER: S-EPMC6009172 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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The first Pd-catalyzed Buchwald-Hartwig aminations at C-2 or C-4 in the estrone series.

Bacsa Ildikó I Szemerédi Dávid D Wölfling János J Schneider Gyula G Fekete Lilla L Mernyák Erzsébet E

Beilstein journal of organic chemistry 20180504

A facile Pd-catalyzed C(sp2)-N coupling to provide a range of 2- or 4-[(subst.)phenyl]amino-13α-estrone derivatives has been achieved under microwave irradiation. The reactions were mediated with the use of Pd(OAc)2 as a catalyst and KOt-Bu as a base in the presence of X-Phos as a ligand. The desired products have been obtained in good to excellent yields. The nature and the position of the aniline substituent at the aromatic ring influenced the outcome of the coupli ...[more]

PMID: 29977371

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