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Spirocyclic diindenothiophenes were prepared by cyclization of tosylhydrazones, readily available from ketones, with 3,4-dibromo-2,5-bis(2-bromphenyl)thiophene. For bicyclic ketones, the bis-spirocycles were formed with very good diastereoselectivity. [ABSTRACT FROM AUTHOR]

A straightforward, site-selective arylation of the bis(triflate) of estrone by Suzuki–Miyaura reactions has been developed. Monoarylation occurs selectively at the D-ring with good to excellent yield. Such products were exemplarily employed for the synthesis of estrones containing two different aryl substituents. [ABSTRACT FROM AUTHOR]

1,4-Diaryl-9H-fluoren-9-ones were prepared by regioselective Suzuki-Miyaura cross-coupling reaction of the bis(triflate) of 1,4-dihydroxy-9H-fluoren-9-one. The reactions proceeded with excellent site selectivity. The first attack occurs at position 1, due to electronic reasons. [ABSTRACT FROM AUTHOR]

8-Aryl- and 6,8-diarylflavones were prepared by Suzuki- Miyaura reactions of 6,8-dibromoflavone. In spite of the greater steric hindrance, the first attack proceeded with good site selectivity at position 8. [ABSTRACT FROM AUTHOR]

Arylated isoflavones are prepared by Suzuki-Miyaura crosscoupling reactions of the bis(triflate) of 4',7-dihydroxyisoflavone. The reactions proceed with very good regioselectivity in favor of the electronically more deficient position. [ABSTRACT FROM AUTHOR]

Sonogashira reactions of steroids have been studied. The reaction of a-estron-16-methylidenyloxy triflate with various alkynes afforded novel alkynylvinylidene steroids. The reactions proceeded in good to quantitative yields, with excellent E-selectivity and with a broad synthetic scope. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed one-pot reaction for the synthesis of benzo[b]carbazolediones is described which proceeds by amination of 2,3-dibromonaphthoquinone, Suzuki cross-coupling with (2-bromophenyl) boronic acid, and subsequent intramolecular C-N Buchwald- Hartwig cyclization with amines. [ABSTRACT FROM AUTHOR]

Arylated naphthalenes were prepared by Suzuki-Miyaura reactions of the bis(triflate) of methyl 3,7-dihydroxy-2-naphthoate. The reactions proceeded with very good site-selectivity in favor of the sterically less hindered position 7, despite the proximity of position 3 to the electron-withdrawing ester group which plays a decisive role for the site-selectivity of Suzuki-Miyaura reactions of related substrates. [ABSTRACT FROM AUTHOR]

5,10-Diaryl-11H-benzo[b]fluoren-11-ones were prepared by Suzuki-Miyaura reactions of the bis(triflate) of 5,10-dihydroxy-11H-benzo[b]fluoren-11-one. The reactions proceed with excellent site-selectivity. The first attack occurs at position 10, due to electronic reasons. [ABSTRACT FROM AUTHOR]

The reaction of 3-nitro-4H-chromen-4-one with in situ generated 1-substituted 5-amino-1H-imidazoles affords a set of 1-substituted 6-nitro-3H-imidazo[4,5-b]pyridines which represent potential adenosine deaminase (ADA) inhibitors. Reduction of the nitro group results in the formation of the corresponding 6-amino-3H-imidazo[4,5-b]pyridines. [ABSTRACT FROM AUTHOR]

The first Suzuki-Miyaura reactions of N-protected tribromopyrazoles are reported. Their reaction with three, two, or one equivalents of arylboronic acids afforded 3,4,5-triarylpyrazoles, 3,5-diaryl-4-bromopyrazoles, or 5-aryl-3,4-dibromopyrazoles, respectively. All reactions proceeded with very good site-selectivity. [ABSTRACT FROM AUTHOR]

The first Suzuki-Miyaura reactions of pentachloropyridine are reported. The reaction with two equivalents of arylboronic acids gave 2,6-diaryl-3,4,5-trichloropyridines, while the reaction with one equivalent of arylboronic acid afforded 2-aryl-3,4,5,6-tetrachloropyridines. The one-pot reaction of pentachloropyridine with two different arylboronic acids resulted in the formation of 2,6-diaryl-3,4,5-trichloropyridines containing two different aryl groups. All reactions proceeded with very good site selectivity. [ABSTRACT FROM AUTHOR]

1,2-Diarylanthraquinones were prepared by Suzuki-Miyaura reactions of the bis(triflate) of 1,2-dihydroxyanthraquin�one (alizarin). The reactions proceed with excellent site selectivity. The first attack occurs at the sterically more hindered position 1, due to electronic reasons. [ABSTRACT FROM AUTHOR]

The [4+2] cycloaddition of 1-ethoxy-2-fluoro-1,3-bis(trimethylsilyloxy)-1,3-diene with dimethyl acetylenedicarboxylate (DMAD) afforded dimethyl 4-fluoro-3,5-dihydroxyphthalate. Site-selective Suzuki-Miyaura reactions of its bis(triflate) provide a convenient approach to 3,5-diaryl-4-fluorophthalates. [ABSTRACT FROM AUTHOR]

The first Suzuki-Miyaura reactions of 2,3,5-tribromothiophene are reported. These reactions provide a convenient and site-selective approach to 5-aryl-2,3-dibromothiophenes, 2,5-diaryl-3-bromothiophenes, and 2,3,5-triarylthiophenes. [ABSTRACT FROM AUTHOR]

N-Methyl-2,3,4,5-tetrabromopyrrole is transformed into a variety of alkynyl-substituted pyrroles by regioselective Sonogashira cross-coupling reactions. In this context, the synthesis of the first tri- and tetra(1-alkynyl)pyrroles is reported. [ABSTRACT FROM AUTHOR]

The first fluorine-containing 1,3-bis(silyl enol ethers), 2-fluoro-1,3-bis(trimethylsilyloxy)-1,3-butadienes, have been prepared. Their reaction with electrophiles allows a convenient synthesis of various open-chain and cyclic organofluorine compounds which are not readily available by other methods. [ABSTRACT FROM AUTHOR]

3-Aryl-2-nitroindoles were prepared via CH-activation reactions of N-methyl-2-nitroindole. [ABSTRACT FROM AUTHOR]

7,8-Diarylflavones were prepared by Suzuki-Miyaura reactions of the bis(triflate) of 7,8-dihydroxyflavone. The first attack proceeded with very good site selectivity at position 7, due to steric and electronic reasons. [ABSTRACT FROM AUTHOR]

Functionalized anthraquinones were prepared by domino ‘twofold Heck-6π-electrocyclization’ reactions of 2,3-dibromo�naphthoquinone. [ABSTRACT FROM AUTHOR]

The palladium(0)-catalyzed Suzuki cross-coupling reaction of the bis(triflates) of methyl 2,5-dihydroxybenzoate afforded p-terphenyls. The reactions proceeded with very good site selectivity. The first attack occurred at carbon atom C-5. [ABSTRACT FROM AUTHOR]