Domino synthesis of 4-vinyl-oxazoles - 1,2-rearrangement cascades en route to siphonazole B
(2014) KEMR31 20141Department of Chemistry
- Abstract
- A novel tandem cyclocondensation/1,2-oxazole rearrangement cascade reaction for the synthesis of 4-vinyl oxazoles from γ-chloro-propargylamines was developed and applied towards a short modular synthesis of natural product siphonazole B. The proposed seven-step route, enabled by the use of 4-vinyl oxazoles as precursors for 4-carboxyl oxazoles, would be the shortest to date. Simply removing the cause of a known regioselectivity issue and using a 4-hydroxymethyl-oxazole as a masked 4-carboxyl-oxazole nucleophile solved the problem and enabled the key reaction – a regioselective aldol-type fragment coupling. Due to difficulties of achieving a latestage formal dehydrogenation the strategy was re-evaluated leading to a formal synthesis of... (More)
- A novel tandem cyclocondensation/1,2-oxazole rearrangement cascade reaction for the synthesis of 4-vinyl oxazoles from γ-chloro-propargylamines was developed and applied towards a short modular synthesis of natural product siphonazole B. The proposed seven-step route, enabled by the use of 4-vinyl oxazoles as precursors for 4-carboxyl oxazoles, would be the shortest to date. Simply removing the cause of a known regioselectivity issue and using a 4-hydroxymethyl-oxazole as a masked 4-carboxyl-oxazole nucleophile solved the problem and enabled the key reaction – a regioselective aldol-type fragment coupling. Due to difficulties of achieving a latestage formal dehydrogenation the strategy was re-evaluated leading to a formal synthesis of siphonazole B. Studies towards achieving the last step of the total synthesis – a tandem oxidative amidation/ketone formation are currently underway. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/4647765
- author
- Paulsen, Filip LU
- supervisor
- organization
- course
- KEMR31 20141
- year
- 2014
- type
- H2 - Master's Degree (Two Years)
- subject
- keywords
- organisk kemi, organic chemistry
- language
- English
- id
- 4647765
- date added to LUP
- 2014-09-22 11:04:27
- date last changed
- 2014-09-22 11:04:27
@misc{4647765, abstract = {{A novel tandem cyclocondensation/1,2-oxazole rearrangement cascade reaction for the synthesis of 4-vinyl oxazoles from γ-chloro-propargylamines was developed and applied towards a short modular synthesis of natural product siphonazole B. The proposed seven-step route, enabled by the use of 4-vinyl oxazoles as precursors for 4-carboxyl oxazoles, would be the shortest to date. Simply removing the cause of a known regioselectivity issue and using a 4-hydroxymethyl-oxazole as a masked 4-carboxyl-oxazole nucleophile solved the problem and enabled the key reaction – a regioselective aldol-type fragment coupling. Due to difficulties of achieving a latestage formal dehydrogenation the strategy was re-evaluated leading to a formal synthesis of siphonazole B. Studies towards achieving the last step of the total synthesis – a tandem oxidative amidation/ketone formation are currently underway.}}, author = {{Paulsen, Filip}}, language = {{eng}}, note = {{Student Paper}}, title = {{Domino synthesis of 4-vinyl-oxazoles - 1,2-rearrangement cascades en route to siphonazole B}}, year = {{2014}}, }