Totalsynthese optisch aktiver Steroide, XIV: Synthese von Östradiol

Eder, Ulrich; Gibian, Heinz; Haffer, Gregor; Neef, Günter; Sauer, Gerhard; Wiechert, Rudolf

doi:10.1002/cber.19761090829

Cited by 34 publications

(14 citation statements)

References 4 publications

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“…For a long time, the only known example of a Robinson annulation procedure that was able to fulfill these major criterions of reactivity as well as regio‐ and stereoselectivities was the transformation of cyclic 1,3‐diketones to give steroid and terpene intermediates (Hajos‐Parish‐Eder‐Sauer‐Wiechert (HPESW) as well as Wieland‐Miescher (WM) ketones) . In addition to their specific reactivity, such annulation reactions involving a symmetrical 1,3‐diketone yield an achiral adduct (isolated or not) in the first Michael addition step (Figure ).…”

Section: Introductionmentioning

confidence: 99%

Enantioselective Access to Robinson Annulation Products and Michael Adducts as Precursors

2017

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The Robinson annulation is a reaction that has been useful for numerous syntheses since its discovery in 1935, especially in the field of steroid synthesis. The products are usually obtained after three consecutive steps: the formation of an enolate (or derivative), a conjugate addition, and an aldol reaction. Over the years, several methodological improvements have been made for each individual step or alternative routes have been devised to access the Robinson annulation products. The first part of this Review outlines the most relevant developments towards the formation of monocarbonyl-derived Robinson annulation products (MRA products, MRAPs) and activated monocarbonyl-derived Robinson annulation products (AMRA products, AMRAPs). The following sections are then devoted to the diastereoselective and enantioselective synthesis of these products, while the last section describes the enantiomeric resolution of racemic mixtures.

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Section: Introductionmentioning

confidence: 99%

Enantioselective Access to Robinson Annulation Products and Michael Adducts as Precursors

2017

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“…Die in dieser Arbeit beschriebene Synthese weist einen Schlusselschritt auf, wie ihn neulich Eder et al [9] zur Totalsynthese von Ostradiol benutzt haben, und welcher in der Verknupfung eines optisch aktiven Bausteins fur die Ringe C und D rnit rn-Methoxyphenacylbromid (4) als AB-Teil besteht. Als Baustein fur die Ringe C und D bot sich das neuerdings durch asymmetrische Synthese leicht zugangliche (S)-konfigurierte Octalindion 1 [ 101 an.…”

Section: Discussionunclassified

Totalsynthese von (+)‐D‐Homoöstron‐3‐methyläther

Gutzwiller

Meier

Fürst

1977

Helvetica Chimica Acta

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Total Synthesis of (+)-D-Homoestrone 3-methyl ether SummaryA novel total synthesis of (+)-D-homoestrone 3-methyl ether (21) is described starting from (S)-8a-methyl-3,4,8,8a-tetrahydro-2H,7H-naphthalene-1,6-dione (1) as a chiral synthon for the rings C and D. The key step involves alkylation of the derived 3 with rn-methoxyphenacyl bromide (4) as an AB-building block to give the dioxo-secosteroid 5. Hydrogenation of 5 affords the trans-decalone 11. As by-products the epimeric cis-decalones 12 and 13 were characterized. Cyclization of 11 leads under kinetic control predominantly to the A9(")-tetraene 14. Catalytic hydrogenation of 14 and subsequent modification in ring D give the title compound 21. It was found that 14 and also the derived As-isomer 15a add hydrogen from the a-face of the molecule to an extent of about 80%. The 8a-D-homoestrone derivatives 20a and 23 as well as the 9p-isomers 19a and 22 were characterized.

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“…[6a,c,e] Only the use of highly S  2 reactive [7] electrophiles like -bromoacetophenone affords the 4-substituted hexahydroinden-5-ones in reasonable yields. [8] In an extension of our previously reported method for the synthesis of 4-substituted hexahydroindene-5-ones 4 by thioalkylation of zinc dienolate 2, [9] we report here the synthesis of 4-substituted hexahydroinden-5-ols 6 and their corresponding hexahydroindene derivatives 10 by in situ reduction of the initially formed 4-substituted hexahydroindene-5-ones 4.…”

Section: Introductionmentioning

confidence: 89%

α-Thioalkylation of Zinc Dienolates as an Entry to 4-Substituted 1-tert-Butoxy-7a-methylhexahydroindenes

2015

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Hexahydroindenes 10 are readily available in 3 steps with an overall yield of 41 – 45 % starting from the Hajos Wiechert ketone 1. Alkylation of the α,β-unsaturated ketone 1 at C-4 has been achieved by thioalkylation of the corresponding zinc dienolate 2 with α-chlorosulfides of type 3. Subsequent in situ reduction and desulfurization of the β-(phenylthio) ketones 4 leads directly to the 4-substituted hexahydroindene-5-ols 6 which can be deoxygenated via their mesylates to the hexahydroindenes 10.

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Totalsynthese optisch aktiver Steroide, XIV: Synthese von Östradiol

Cited by 34 publications

References 4 publications

Enantioselective Access to Robinson Annulation Products and Michael Adducts as Precursors

Enantioselective Access to Robinson Annulation Products and Michael Adducts as Precursors

Totalsynthese von (+)‐D‐Homoöstron‐3‐methyläther

α-Thioalkylation of Zinc Dienolates as an Entry to 4-Substituted 1-tert-Butoxy-7a-methylhexahydroindenes

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