Total synthesis of certain hydrochrysene analogues
department or school: Science, Faculty of
department or school: Chemistry, Department of
data provider: DSpace
degree campus: UBCV
creator: Inaba, Tadanobu
issued: 2011-09-26T23:38:25Z
issued: 1964
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: A sequence leading to the total synthesis of certain derivatives in the 11, 12-seco (see XXIV) and 5, 6-seco hydro-chrysene (see XXXI) series is described. The synthesis employs in its initial stages the Robinson-Mannich base reaction and the Michael condensation reaction to construct the parent tetracyclic skeleton. Condensation of 6-methoxy-2-tetralone with 1-diethylamino-3-pentanone methiodide produced an isomeric mixture of tricyclic ketones. This mixture was then condensed with methyl vinyl ketone to yield a tetracyclic ketol (XII) which in turn was converted to the tetracyclic ketone (XIII) by reaction with sodium methoxide. By appropriate modifications, this latter substance may then be utilized for the synthesis of a variety of hydrochrysene analogues. Oxidation of trans-anti-trans-2-methoxy-8β-acetoxy-10a -methyl-4b, 5, 6, 6a, 7, 8, 9, 10, 10a, 10b, 11, 12-dodecahydrochrysene (XVI) with t-butyl chromate solution gave not only the 12-keto derivative (XIX), but the 5-keto octahydrochrysene analogue (XX) as well as small amounts of the octahydrochrysene (XVII) and the hexahydrochrysene analogue (XVIII). The olefinic bond at the 11, 12 position of ring C (XXII) was introduced by reduction of the 12-keto derivative (XIX) with sodium borohydride, followed by dehydration with phosphorus pentoxide. Subsequent ozonization of XXII yielded the dialde-hyde (XXIV). The olefinic bond at the 5, 6 position of ring B (XVIII) was introduced by the same procedure as in the ring C series. This hexahydrochrysene analogue (XVIII) was reacted with osmium tetroxide to provide the diol (XXVI), which upon treatment with periodic acid yielded the aldol condensation product directly without isolation of the dialdehyde. Nuclear magnetic resonance (n. m. r.) spectroscopy was found to be a powerful tool for the purpose of the characterization of these rather complex molecules.
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/37627
note: TOTAL SYNTHESIS OF CERTAIN HYDROCHRYSENE ANALOGUES by TADANOBU INABA B.Eng., U n i v e r s i t y of Osaka Pref., 1962 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE i n the Department of Chemistry We accept t h i s t h e s i s as conforming to the requ i r e d standard THE UNIVERSITY OF BRITISH COLUMBIA August, 1964 In p r e s e n t i n g t h i s t h e s i s i n p a r t i a l f u l f i l m e n t of the requirements f o r an advanced degree at the U n i v e r s i t y of • B r i t i s h Columbia, I agree that the L i b r a r y s h a l l make i t f r e e l y a v a i l a b l e f o r r e f e r e n c e and study* I f u r t h e r agree that per-m i s s i o n f o r extensive copying of t h i s t h e s i s f o r s c h o l a r l y • purposes may be granted by.the Head of my Department or by h i s r e p r e s e n t a t i v e s . .It i s understood t h a t ; c o p y i n g or p u b l i -c a t i o n of t h i s t h e s i s f o r f i n a n c i a l gain s h a l l not be allowed without my w r i t t e n permission* Department 1 of CHEMISTRY The U n i v e r s i t y . o f B r i t i s h Columbia, Vancouver 8. Canada Date >t=^T . J©. l i l t ( i i i ) ABSTRACT A sequence leading to the t o t a l synthesis of c e r t a i n derivatives i n the 11, 12-seco (see XXIV) and 5, 6-seco hydro-chrysene (see XXXl) series i s described. The synthesis.employs i n i t s i n i t i a l stages the Robinson-Mannich base reaction and the Michael condensation reaction to construct the parent t e t r a c y c l i c skeleton. Condensation of 6-methoxy-2-tetralone with l-diethylamino -3-pentanone methiodide produced an isomeric mixture of t r i c y c l i c ketones. This mixture was then condensed with methyl v i n y l ketone to y i e l d a t e t r a c y c l i c k e t o l (XII) which i n turn was converted to the t e t r a c y c l i c ketone (XIIl) by reaction with sodium methoxide. By appropriate modifications, th i s l a t t e r substance may then be u t i l i …
has type: Thesis/Dissertation
is shown at: 10.14288/1.0062224
language: eng
degree discipline: Chemistry
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/37627