Resumen: The aromatic osmacyclopropenefuran bicycles [OsTp{¿3-C1,C2,O-(C1H2C2CHC(OEt)O)}(PiPr3)]BF4 (Tp=hydridotris(1-pyrazolyl)borate) and [OsH{¿3-C1,C2,O-(C1H2C2CHC(OEt)O)}(CO)(PiPr3)2]BF4, with the metal fragment in a common vertex between the fused three- and five-membered rings, have been prepared via the p-allene intermediates [OsTp(¿2-CH2=CCHCO2Et)(OCMe2)(PiPr3)]BF4 and [OsH(¿2-CH2=CCHCO2Et)(CO)(OH2)(PiPr3)2]BF4, and their aromaticity analyzed by DFT calculations. The bicycle containing the [OsH(CO)(PiPr3)2]+ metal fragment is a key intermediate in the [OsH(CO)(OH2)2(PiPr3)2]BF4-catalyzed regioselective anti-Markovnikov hydration of ethyl buta-2,3-dienoate to ethyl 4-hydroxycrotonate. Idioma: Inglés DOI: 10.1002/anie.201606839 Año: 2016 Publicado en: Angewandte Chemie (International ed.) 55, 44 (2016), 13749-13753 ISSN: 1433-7851 Factor impacto JCR: 11.994 (2016) Categ. JCR: CHEMISTRY, MULTIDISCIPLINARY rank: 13 / 166 = 0.078 (2016) - Q1 - T1 Factor impacto SCIMAGO: 5.953 - Chemistry (miscellaneous) (Q1) - Catalysis (Q1)