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Palladium-catalyzed asymmetric allylic substitution of 2-arylcyclohexenol derivatives: asymmetric total syntheses of (+)-crinamine, (-)-haemanthidine, and (+)-pretazettine.
J Org Chem. 2004 Mar 19; 69(6):1837-43.JO

Abstract

Much interest has been shown in Amaryllidaceae alkaloids as synthetic targets due to their wide range of biological activities. Over 100 alkaloids have been isolated from members of the Amaryllidaceae family; most of them can be classified into eight skeletally homogeneous groups. We have succeeded in the first asymmetric total syntheses of the crinane-type alkaloids (+)-crinamine (1), (-)-haemanthidine (2), and (+)-pretazettine (3). The starting cyclohexenylamine 14 was obtained from allyl phosphonate 11c by palladium-catalyzed asymmetric amination in 82% yield and with 74% ee. The product was recrystallized from MeOH. Interestingly, (-)-14 with 99% ee was obtained from the mother liquor (74% recovery). Intramolecular carbonyl-ene reaction of (-)-10 proceeds in a highly stereoselective manner to give hexahydroindole derivative 9 as the sole product. In the Lewis-acid-catalyzed carbonyl-ene reaction, an interesting rearrangement product, 20, was isolated in high yield. From 9, (+)-crinamine was synthesized. Thus, the asymmetric total synthesis of (+)-crinamine was achieved in 10 steps from 11c, and the overall yield is 19%. The total synthesis of (-)-haemanthidine was also achieved from 9 by a short sequence of steps.

Authors+Show Affiliations

Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.No affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

15058926

Citation

Nishimata, Toyoki, et al. "Palladium-catalyzed Asymmetric Allylic Substitution of 2-arylcyclohexenol Derivatives: Asymmetric Total Syntheses of (+)-crinamine, (-)-haemanthidine, and (+)-pretazettine." The Journal of Organic Chemistry, vol. 69, no. 6, 2004, pp. 1837-43.
Nishimata T, Sato Y, Mori M. Palladium-catalyzed asymmetric allylic substitution of 2-arylcyclohexenol derivatives: asymmetric total syntheses of (+)-crinamine, (-)-haemanthidine, and (+)-pretazettine. J Org Chem. 2004;69(6):1837-43.
Nishimata, T., Sato, Y., & Mori, M. (2004). Palladium-catalyzed asymmetric allylic substitution of 2-arylcyclohexenol derivatives: asymmetric total syntheses of (+)-crinamine, (-)-haemanthidine, and (+)-pretazettine. The Journal of Organic Chemistry, 69(6), 1837-43.
Nishimata T, Sato Y, Mori M. Palladium-catalyzed Asymmetric Allylic Substitution of 2-arylcyclohexenol Derivatives: Asymmetric Total Syntheses of (+)-crinamine, (-)-haemanthidine, and (+)-pretazettine. J Org Chem. 2004 Mar 19;69(6):1837-43. PubMed PMID: 15058926.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Palladium-catalyzed asymmetric allylic substitution of 2-arylcyclohexenol derivatives: asymmetric total syntheses of (+)-crinamine, (-)-haemanthidine, and (+)-pretazettine. AU - Nishimata,Toyoki, AU - Sato,Yoshihiro, AU - Mori,Miwako, PY - 2004/4/3/pubmed PY - 2004/5/28/medline PY - 2004/4/3/entrez SP - 1837 EP - 43 JF - The Journal of organic chemistry JO - J Org Chem VL - 69 IS - 6 N2 - Much interest has been shown in Amaryllidaceae alkaloids as synthetic targets due to their wide range of biological activities. Over 100 alkaloids have been isolated from members of the Amaryllidaceae family; most of them can be classified into eight skeletally homogeneous groups. We have succeeded in the first asymmetric total syntheses of the crinane-type alkaloids (+)-crinamine (1), (-)-haemanthidine (2), and (+)-pretazettine (3). The starting cyclohexenylamine 14 was obtained from allyl phosphonate 11c by palladium-catalyzed asymmetric amination in 82% yield and with 74% ee. The product was recrystallized from MeOH. Interestingly, (-)-14 with 99% ee was obtained from the mother liquor (74% recovery). Intramolecular carbonyl-ene reaction of (-)-10 proceeds in a highly stereoselective manner to give hexahydroindole derivative 9 as the sole product. In the Lewis-acid-catalyzed carbonyl-ene reaction, an interesting rearrangement product, 20, was isolated in high yield. From 9, (+)-crinamine was synthesized. Thus, the asymmetric total synthesis of (+)-crinamine was achieved in 10 steps from 11c, and the overall yield is 19%. The total synthesis of (-)-haemanthidine was also achieved from 9 by a short sequence of steps. SN - 0022-3263 UR - https://www.unboundmedicine.com/medline/citation/15058926/Palladium_catalyzed_asymmetric_allylic_substitution_of_2_arylcyclohexenol_derivatives:_asymmetric_total_syntheses_of__+__crinamine_____haemanthidine_and__+__pretazettine_ DB - PRIME DP - Unbound Medicine ER -