Stereoselective hydrogenation of conjugate diene directed by hydroxy group and asymmetric synthesis of deoxypolypropionate units

Formal Aromatic C−H Insertion for Stereoselective Isoquinolinone Synthesis and Studies on Mechanistic Insights into the C−C Bond Formation

“…Isoquinolinone products were obtained as minor products for carbenoids 4 and 5 and the major products of the reactions were cycloheptapyrrolones 10 , 11 , and 12 . The major products were formed via ring expansion of the cyclopropanated intermediate as the Buchner reaction …”

“…Analogous to our approach toward aliphatic C−H insertion, we postulated that a bulky “relatively electron-rich” carbenoid as a α-substituent would enable a thermodynamically controlled reaction pathway, while averting cycloheptapyrrolone formation via an intramolecular Buchner reaction . We selected phenylsulfonyl and ethoxyphosphoryl groups as the candidates for the reactions.…”

“…Several successful examples of five-membered ring formation without disrupting aromatic resonance have been reported (eq ) . However, in reports for the construction of a six-membered ring, such as isoquinolinone, formation of a 7,5-bicyclic structure via cyclopropanation on the aromatic ring was also observed (eq ) . Although isoquinolinone formation with diazoacetamides and protic acid has been reported, the reaction was only applicable to limited substrates and was not regioselective .…”

Catalytic Asymmetric Synthesis of Allylic Alcohols and Derivatives and their Applications in Organic Synthesis

“…[1] Examples include aziridination, [2,3] Simmons-Smith-type cyclopropanation, [4,5] epoxidation, [6] hydrogenation, [7,8] Paterno-Büchi reaction, [9] dihydroxylation, [10] and singlet oxygen-mediated oxidation (Scheme 1). When enantiopure allylic alcohols are employed, a variety of highly diastereoselective reactions can be used to form building blocks with up to three contiguous stereocenters (Scheme 1).…”

“…In many of these transformations the alcohol (or alkoxide) serves as a directing group and ensures a high level of selectivity. [1] Examples include aziridination, [2,3] Simmons-Smith-type cyclopropanation, [4,5] epoxidation, [6] hydrogenation, [7,8] Paterno-Büchi reaction, [9] dihydroxylation, [10] and singlet oxygen-mediated oxidation (Scheme 1). [11] Furthermore, the allylic hydroxy group can also direct a variety of olefin metathesis reactions such as ring-closing metathesis (RCM), cross-metathesis (CM), and ring-opening cross-metathesis (ROCM), which enhance both the selectivity and the rate of reaction (Scheme 2).…”