Summarized in this article are the syntheses of heterocyclic natural products by means of Rh-catalyzed C-H insertion reaction of diazoester. During the course of our total synthesis of (−)-ephedradine A (
1) by application of Ns-strategy, we found that the Rh
2(
S-DOSP)
4 mediated C-H insertion reaction was enabled to simplify the synthetic process and decided to use it for the natural product synthesis. In the synthesis of serotobenine (
4), the C-H insertion precursor was efficiently synthesized by the Leimgruber-Batcho protocol and a regioselective Claisen rearrangement. The racemic nature of serotobenine (
4) is suggested by the presence of
p-quinonemethide intermediate
6. Enantioselective synthesis of SB-203207 (
25a) was accomplished by desymmetric C-H insertion reaction of
33 for construction of a bicyclo[3.3.0] framework, stereoselective construction of sequential stereocenters of
37, novel conversion from an aldehyde to a carboxylic acid, and nitrile hydrolysis. Stereoselective synthesis of MFPA (
54) was accomplished by intermolecular C-H insertion and the asymmetric center at the benzylic position of
58 permitted efficient incorporation of the three sequential stereochemistries on the pyrrolidine ring of
68. Synthesis of aperidine (
70) was featured by the
cis-selective construction of a dihydrobenzofuran ring of
82 utilizing by Hashimoto’s catalyst and preparation of diazoamide of
81 by Raines’ protocol.
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