The intramolecular aldol condensation of 3-oxocyclohexaneacetaldehydes: a useful tool in the synthesis of natural products

A new preparation and the isolation and spectroscopic characterization of 1,3,3-trimethylbicyclo[2.2.2]octan-2,6-dione (3), a so far elusive key intermediate in the LiuÀRalitsch total synthesis of ()-norpatchoulenol (()-1a), is described. The preparation of 3 constitutes also a formal total synthesis of (AE)-iso-norpatchoulenol ((AE)-1b), since 3 is correlated to an intermediate in the Monti and co-workers synthesis of (AE)-1b.

show abstract

A New Preparation of 1,3,3‐Trimethylbicyclo[2.2.2]octan‐2,6‐dione, a Never Isolated Intermediate in a Total Synthesis of (+)‐Norpatchoulenol. Formal Total Synthesis of (±)‐Iso‐Norpatchoulenol

Bella

Leonelli²,

Salve

et al. 2004

Helvetica Chimica Acta

View full text Add to dashboard Cite

show abstract

Synthesis of (+)‐13‐Stemarene and (+)‐18‐Deoxystemarin: Expeditious Preparation of the Key 6‐exo‐Hydroxybicyclo[2.2.2]octan‐2‐one Ethylene Dithioacetal

Leonelli

Caschera

Silvestri

et al. 2008

Helvetica Chimica Acta

Self Cite

View full text Add to dashboard Cite

An expeditious preparation of the 6-exo-hydroxybicyclo[2.2.2]octan-2-one ethylene dithioacetal 2b, a key intermediate in the synthesis of (þ)-13-stemarene (4) and (þ)-18-deoxystemarin (5) is described. Compound 2b was obtained as the major product by equilibrating the endo rich mixture of 6-hydroxybicyclo[2.2.2]octan-2-one ethylene dithioacetals 2 with TsOH in benzene at reflux, easily available from the corresponding hydroxy ketones 9. The model experiments which preceeded the above transformation, not previously described in the literature, are also presented.Introduction. By Raney-Ni desulfurization, hydroxydithioacetals 1 and 2b were in fact transformed into bicyclo[2.2.2]octan-2-ols 6 and 7, and the latter rearranged 3 ) to the stemarane system (Scheme 1).Compounds 1 and 2b were efficiently prepared from the corresponding 6-exohydroxybicyclo[2.2.2]octan-2-ones 8 and 9b by thioacetalization with 1,2-ethanedithiol in the presence of BF 3 · Et 2 O [2] [6]. Given that 6-exo-hydroxybicyclo[2.2.2]octan-2-ones of the type of 8 and 9b are the minor products (endo/exo 85 : 15) of the intramolecular aldol condensation of a 3-oxocyclohexaneacetaldehyde [7] [8] (Scheme 2), the efficiency of the synthesis of stemarane diterpenoids, by this approach,

show abstract

Kinetics and mechanism of intramolecular aldol condensation of 2,5-hexadione, a DFT and MP2 study

Zardoost

2013

Russ. J. Phys. Chem. B

View full text Add to dashboard Cite

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

customersupport@researchsolutions.com

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

The intramolecular aldol condensation of 3-oxocyclohexaneacetaldehydes: a useful tool in the synthesis of natural products

Cited by 5 publications

References 3 publications

A New Preparation of 1,3,3‐Trimethylbicyclo[2.2.2]octan‐2,6‐dione, a Never Isolated Intermediate in a Total Synthesis of (+)‐Norpatchoulenol. Formal Total Synthesis of (±)‐Iso‐Norpatchoulenol

A New Preparation of 1,3,3‐Trimethylbicyclo[2.2.2]octan‐2,6‐dione, a Never Isolated Intermediate in a Total Synthesis of (+)‐Norpatchoulenol. Formal Total Synthesis of (±)‐Iso‐Norpatchoulenol

Synthesis of (+)‐13‐Stemarene and (+)‐18‐Deoxystemarin: Expeditious Preparation of the Key 6‐exo‐Hydroxybicyclo[2.2.2]octan‐2‐one Ethylene Dithioacetal

Kinetics and mechanism of intramolecular aldol condensation of 2,5-hexadione, a DFT and MP2 study

Contact Info

Product

Resources

About