Enantiomerically pure cyclobutane derivatives and their use in organic synthesis.

[Song, Zhen-Lei] Sichuan Univ, Key Lab Drug Targeting, Educ Minist, Dept Med Chem,W China Sch Pharm, Chengdu 610041, Peoples R China

Semipinacol rearrangement in natural product synthesis.

This review describes the development of enantioselective methods for the ring opening of cyclopropanes. Both approaches based on the reaction of nonchiral cyclopropanes and (dynamic) kinetic resolutions and asymmetric transformations of chiral substrates are presented. The review is organized according to substrate classes, starting by the more mature field of donor-acceptor cyclopropanes. Emerging methods for enantioselective ring opening of acceptor- or donor-only cyclopropanes are then presented. The last part of the review describes the ring opening of more reactive three-membered rings substituted with unsaturations with a particular focus on vinylcyclopropanes, alkylidenecyclopropanes, and vinylidenecyclopropanes. In the last two decades, the field has grown from a proof of concept stage to a broad range of methods for accessing enantioenriched building blocks, and further extensive developments can be expected in the future.

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Catalytic Enantioselective Ring-Opening Reactions of Cyclopropanes.

A novel and efficient route to chiral A-ring aromatic trichothecanes—The first enantiocontrolled total synthesis of (-)-debromofiliformin and (-)-filiformin

A novel and convenient route to the thermodynamically unstable ketone 11via the cyclopentanone 8 which was synthesised by palladium-mediated ring expansion of the chiral siloxyvinylcyclobutanes 9 and 10 has been developed. This leads to an enantioselective total synthesis of (+)- laurene 1.

Chiral cyclobutanones as versatile synthons: the first enantioselective total synthesis of (+)-laurene

A concise enantiocontrolled synthesis of (+)-(5S, 2R)- and (+)-(5R, 2R)-5-(3-furyl)-2-iodomethyl-2-methyloxolanes, (6) and (5), was achieved starting from (+)-(R)-2-hydroxymethyl-2-methylcyclobutanone (11) which was efficiently prepared by the tandem asymmetric epoxidation and 1,2-rearrangement of 2-cyclopropylidenepropanol (9). This constitutes an enantiocontrolled formal total synthesis of (+)-ipomeamarone (1), (+)-epiipomeamarone (2), (-)-ngaione (3) and its epimer (4)

T. Tanabe

Papers

An enantiocontrolled formal total synthesis of (+)-ipomeamarone, (-)-ngaione, and their epimers

An Enantiocontrolled Formal Total Synthesis of (+)-Ipomeamarone, (-)- Ngaione, and Their Epimers.