Abstract
A study of alkali metal amide-mediated isomerizations of terminal allenes is described. The isomerizations of substituted ethenylidenecyclohexanes to form diastereomeric mixtures of terminal alkynes have been conducted to determine factors which may influence the stereochemistry at the newly formed propargylic centers. An initial base screen revealed that potassium N-methylbutylamide (KMBA) exhibits the highest level of equatorial to axial alkyne diastereoselectivity. With the severely hindered terminal allene 26, the use of potassium 3-aminopropylamide is required to effect isomerization. A general synthesis of deuterated terminal allenes has also been achieved, and a mechanistic study using d2-allenes 18a,b has revealed the involvement of a propargylic anion in the course of the KMBA-mediated isomerizations.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 4014-4021 |
| Number of pages | 8 |
| Journal | Journal of Organic Chemistry |
| Volume | 61 |
| Issue number | 12 |
| State | Published - Jun 14 1996 |
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ASJC Scopus subject areas
- Organic Chemistry
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Stereogenic propargylic centers via base-mediated terminal allne isomerization. / Spence, John D.; Wyatt, Justin K.; Bender, Daniel M.; Moss, David K.; Nantz, Michael H.
In: Journal of Organic Chemistry, Vol. 61, No. 12, 14.06.1996, p. 4014-4021.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Stereogenic propargylic centers via base-mediated terminal allne isomerization
AU - Spence, John D.
AU - Wyatt, Justin K.
AU - Bender, Daniel M.
AU - Moss, David K.
AU - Nantz, Michael H.
PY - 1996/6/14
Y1 - 1996/6/14
N2 - A study of alkali metal amide-mediated isomerizations of terminal allenes is described. The isomerizations of substituted ethenylidenecyclohexanes to form diastereomeric mixtures of terminal alkynes have been conducted to determine factors which may influence the stereochemistry at the newly formed propargylic centers. An initial base screen revealed that potassium N-methylbutylamide (KMBA) exhibits the highest level of equatorial to axial alkyne diastereoselectivity. With the severely hindered terminal allene 26, the use of potassium 3-aminopropylamide is required to effect isomerization. A general synthesis of deuterated terminal allenes has also been achieved, and a mechanistic study using d2-allenes 18a,b has revealed the involvement of a propargylic anion in the course of the KMBA-mediated isomerizations.
AB - A study of alkali metal amide-mediated isomerizations of terminal allenes is described. The isomerizations of substituted ethenylidenecyclohexanes to form diastereomeric mixtures of terminal alkynes have been conducted to determine factors which may influence the stereochemistry at the newly formed propargylic centers. An initial base screen revealed that potassium N-methylbutylamide (KMBA) exhibits the highest level of equatorial to axial alkyne diastereoselectivity. With the severely hindered terminal allene 26, the use of potassium 3-aminopropylamide is required to effect isomerization. A general synthesis of deuterated terminal allenes has also been achieved, and a mechanistic study using d2-allenes 18a,b has revealed the involvement of a propargylic anion in the course of the KMBA-mediated isomerizations.
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UR - http://www.scopus.com/inward/citedby.url?scp=0000431936&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:0000431936
VL - 61
SP - 4014
EP - 4021
JO - Journal of Organic Chemistry
JF - Journal of Organic Chemistry
SN - 0022-3263
IS - 12
ER -