Novel construction of steroid skeleton. Utility of di-tert-butyl acetonedicarboxylate

Crawley, L.; Solomon, Daniel M.; Heggs, P.

doi:10.1021/ja00738a063

Cited by 16 publications

(1 citation statement)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Another interesting new approach to total synthesis [164,165] has, as its key intermediate, the triketone 235 ( Scheme 12-28 ), prepared from the sodium salt of 2-methylcyclopentane-l,3-dione and 234 by Michael addition and subsequent dehydrohalogenation (Michael addition of divinyl ketone and 12 to afford 235 was not successful). A two-stage condensation (potassium f-butoxide in f-butanol followed by p-toluenesulfonic acid-acetic acid) of 235 and 236 produced the tricyclic 238.…”

Section: Miscellaneous Synthesesmentioning

confidence: 99%

Cd → BCD → Abcd

1974

Organic Chemistry: A Series of Monographs

View full text Add to dashboard Cite

The starting CD intermediates for the various total syntheses outlined in this chapter and in Chapter 7 are often the same or quite analogous. Historically, a large effort has been expended in the preparation of such material, both in the context of steroid synthesis and, recently, as a goal unto itself. A discussion of the pathways developed for the synthesis of CD intermediates has been included at this point such that later, when the individual total synthetic schemes are presented, it will be unnecessary to outline the preparation of the starting materials, except in those cases where unique pathways have been developed.Most of the early synthetic plans started with appropriate naphthalene derivatives which in turn gave rise to D-homosteroids. For example, Johnson's estrone synthesis started with decalin-l,5-dione (3, Scheme 12-1) which had earlier been prepared from 1,5-dihydroxynaphthalene (58%) [1], By modifying the previously employed conditions to include Raney nickel hydrogénation at elevated temperatures and pressures in a basic ethanolic solution, it was possible to obtain a mixture of diols, 2 (stereochemistry undetermined), which, without purification, could be oxidized to a mixture of eis and trans diketones 3 [2], The yield for this conversion (l-»3) was 55% and, for synthetic purposes, the mixture 239 O OH J Φ-,ύ^.

show abstract

Section: Miscellaneous Synthesesmentioning

confidence: 99%