Carbonyl Allylation in the Absence of Preformed Allyl Metal Reagents: Reverse Prenylation via Iridium-Catalyzed Hydrogenative Coupling of Dimethylallene
摘要:
Iridium-catalyzed hydrogenation of dimethylallene in the presence of aromatic, heteroaromatic, and aliphatic carbonyl electrophiles 1a-12a delivers products of reverse prenylation 1b-12b. Reductive coupling of dimethyl allene to aldehyde 8a under an atmosphere of deuterium provides deuterio -8b. As revealed by H-2 NMR analysis, deuterium incorporation is observed at the vinylic position (80% H-2). Unlike established methods for carbonyl allylation, the present protocol circumvents the use of stoichiometrically preformed organometallic reagents.
Carbonyl Allylation in the Absence of Preformed Allyl Metal Reagents: Reverse Prenylation via Iridium-Catalyzed Hydrogenative Coupling of Dimethylallene
作者:Eduardas Skucas、John F. Bower、Michael J. Krische
DOI:10.1021/ja075971u
日期:2007.10.1
Iridium-catalyzed hydrogenation of dimethylallene in the presence of aromatic, heteroaromatic, and aliphatic carbonyl electrophiles 1a-12a delivers products of reverse prenylation 1b-12b. Reductive coupling of dimethyl allene to aldehyde 8a under an atmosphere of deuterium provides deuterio -8b. As revealed by H-2 NMR analysis, deuterium incorporation is observed at the vinylic position (80% H-2). Unlike established methods for carbonyl allylation, the present protocol circumvents the use of stoichiometrically preformed organometallic reagents.
Radical Addition-Enabled C–C σ-Bond Cleavage/Reconstruction to Access Functional Indanones: Total Synthesis of Carexane L
modification in syntheticchemistry but it remains a formidable challenge to perform on unstrained skeletons. Herein, we describe a radical addition-enabled C–C σ-bond cleavage/reconstruction reaction of unstrained allyl ketones to access various functional indanones bearing a benzylic quaternary center. The synthetic utility of this method has been showcased by the first total synthesis of carexane L, an indanone-based
C-C σ 键断裂和重建是合成化学中结构修饰的重要工具,但在无应变骨架上进行仍然是一个巨大的挑战。在此,我们描述了无张力烯丙基酮的自由基加成C-C σ-键裂解/重建反应,以获得带有苄基四元中心的各种功能性茚满酮。该方法的合成实用性已通过茚满酮天然产物 Carexane L 的首次全合成得到展示。