Gold(III) Porphyrin-Catalyzed Cycloisomerization of Allenones
摘要:
Gold(III) porphyrin-catalyzed cycloisomerization of allenones gave the corresponding furans in good to excellent yields (up to 98%) and with quantitative substrate conversions. By recovering the Au(III) catalyst, a recyclable catalytic system is developed with over 8300 product turnovers attained for the cycloisomerization of 1-phenyl-buta-2,3-dien-1-one. The versatility of the gold(Ill) porphyrin catalyst was exemplified by its application to the hydroamination and hydration of phenylacetylene in 73% and 87% yield, respectively.
A bicyclization reaction with two molecular allenyl ketones and isocyanides: synthesis of a lactone-containing azaspirocycle derivative
作者:Hongdong Yuan、Chongrong Tang、Shikuan Su、Lei Cui、Xueshun Jia、Chunju Li、Jian Li
DOI:10.1039/c9cc02785h
日期:——
A novel bicyclization reaction of twomolecular allenyl ketones and isocyanides has been disclosed. This strategy allows for the construction of structurally complex spirocyclic lactam–lactone systems in an efficient manner. This protocol also demonstrates other advantages such as high synthetic efficiency, atom economy, and broad substrate scope under mild conditions.
Isomerizations on silica gel: Synthesis of allenyl ketones and the first Nazarov cyclizations of vinyl allenyl ketones
作者:A Stephen、K Hashmi、Jan W Bats、Ji-Hyun Choi、Lothar Schwarz
DOI:10.1016/s0040-4039(98)01619-0
日期:1998.10
chromatographic workup of crude, terminal propargyl ketones 5 on silica gel directly leads to terminal allenylketones 6. When the other substituent on 5 was electron-rich, 7 was observed as side-product. If the other substituent on 5 was electron-poor, the isomeric 1-propynyl ketone 8 was the side-product. Chromatography of the crude propargyl vinyl ketones 10 on silica gel delivers the products of a Nazarov