2005
DOI: 10.1055/s-2004-836066
|View full text |Cite
|
Sign up to set email alerts
|

Radical Deoxygenation of 3-Azatricyclo[2.2.1.02,6]heptan-5-ols to 1,2-Dihydropyridines

Abstract: Radical deoxygenations of 7-alkyl-1-tosyl-3-azatricyclo[2.2.1.0 2,6 ]heptan-5-ols 9 (R = alkyl) give 7-alkyl-4-tosyl-2-azabicyclo[2.2.1]hept-5-enes 10, whereas 7-aryl-1-tosyl-3-azatricyclo[2.2.1.0 2,6 ]heptan-5-ols 9 (R = aryl) give 2-aryl-5-tosyl-1,2-dihydropyridines 12.Radical cyclisations and rearrangements constitute powerful methodology for the synthesis of ring systems. 1 Radical rearrangements in nortricyclyl (tricyclo[2.2.1.0 2,6 ]heptanyl) and norbornenyl (bicyclo[2.2.1]heptenyl) systems are well-know… Show more

Help me understand this report

Search citation statements

Order By: Relevance

Paper Sections

Select...
2
1
1

Citation Types

0
6
0

Year Published

2005
2005
2020
2020

Publication Types

Select...
7

Relationship

2
5

Authors

Journals

citations
Cited by 7 publications
(6 citation statements)
references
References 7 publications
(7 reference statements)
0
6
0
Order By: Relevance
“…Alternatively, dihydropyridines 326 can be accessed via further rearrangement before the trapping event (Scheme 79A). 246 This methodology has been used to transform 327 to 328, which is a precursor en route to epibatidine analogue 329 (Scheme 79B). 247,248 A related rearrangement strategy was developed for the synthesis of kainoid amino acids.…”
Section: Methodologies Based On Radical Intermediatesmentioning
confidence: 99%
See 1 more Smart Citation
“…Alternatively, dihydropyridines 326 can be accessed via further rearrangement before the trapping event (Scheme 79A). 246 This methodology has been used to transform 327 to 328, which is a precursor en route to epibatidine analogue 329 (Scheme 79B). 247,248 A related rearrangement strategy was developed for the synthesis of kainoid amino acids.…”
Section: Methodologies Based On Radical Intermediatesmentioning
confidence: 99%
“…β-Scission of 323 to 324 is promoted by relief of ring strain, and the resulting radical 324 can be trapped directly by n -Bu 3 SnH to provide 325 . Alternatively, dihydropyridines 326 can be accessed via further rearrangement before the trapping event (Scheme A) . This methodology has been used to transform 327 to 328 , which is a precursor en route to epibatidine analogue 329 (Scheme B). , A related rearrangement strategy was developed for the synthesis of kainoid amino acids .…”
Section: Methodologies Based On Radical Intermediatesmentioning
confidence: 99%
“…Cyclopropane ringopening takes place under typical radical deoxygenation conditions to generate the radical 76, stabilised by the nitrogen atom. Two main types of reactivity are eventually observed: either direct trapping by Bu 3 SnH to produce 2-azabicyclo[2.2.1]hept-5-enes or a further β-fragmentation to produce the radical 77, which finally abstracts a hydrogen atom from Bu 3 SnH to give a dihydropyridine compound(Scheme 50, top) 152,153,154,155,156. The latter reaction pathway operates only when the starting radical precursor bears a radical-stabilising group R 1 (e.g.…”
mentioning
confidence: 99%
“…To investigate the origins of the selectivity for the isomeric azabicycles in the radical addition reaction, xanthate 29 was synthesized for radical deoxygenation (Scheme ). Treatment of epoxide 27 (available via regio- and stereoselective epoxidation of dienyl sulfone 16 ) with t -BuMgCl (3 equiv) led to the formation of tricyclic alcohol 28 (92%) . Attempted radical deoxygenation of the derived xanthate 29 at room temperature using Et 3 B and Bu 3 SnH led only to recovery of the xanthate 29 .…”
Section: Resultsmentioning
confidence: 99%