Rac-2′,3a,6,6,6′,6′-Hexamethyl-3a,3b,6,7-tetra-hydrospiro-[benzo[2,3]cyclopropa[1,2-c]pyrazole-1,1′-cyclo-hepta[2,4]diene]
This note describes a novel reaction cascade in which a tosylhydrazone derivative of eucarvone undergoes a non-classical dimerization process under basic conditions. The key step in this sequence is a dipolar cycloaddition between a diazo species and a transient cyclopropene. A proposed mechanism fo...
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| Format: | Article |
| Language: | English |
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MDPI AG
2017-08-01
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| Series: | Molbank |
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| Online Access: | https://www.mdpi.com/1422-8599/2017/3/M948 |
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doaj-51f13212338d43c3ac0658af7636615a2020-11-24T23:14:52ZengMDPI AGMolbank1422-85992017-08-0120173M94810.3390/M948M948Rac-2′,3a,6,6,6′,6′-Hexamethyl-3a,3b,6,7-tetra-hydrospiro-[benzo[2,3]cyclopropa[1,2-c]pyrazole-1,1′-cyclo-hepta[2,4]diene]Marcus Baumann0Sophie Lapraille1Ian R. Baxendale2Department of Chemistry, University of Durham, South Road, Durham DH1 3LE, UKDepartment of Chemistry, University of Durham, South Road, Durham DH1 3LE, UKDepartment of Chemistry, University of Durham, South Road, Durham DH1 3LE, UKThis note describes a novel reaction cascade in which a tosylhydrazone derivative of eucarvone undergoes a non-classical dimerization process under basic conditions. The key step in this sequence is a dipolar cycloaddition between a diazo species and a transient cyclopropene. A proposed mechanism for this sequence is presented that is supported by single crystal X-ray analysis of the resulting dimer. We believe this unique transformation is of note as it highlights a neat and efficient entry to complex polycyclic architectures containing an embedded pyrazoline moiety.https://www.mdpi.com/1422-8599/2017/3/M948eucarvonedimerizationcycloadditiontosylhydrazone1,3-dipolemolecular rearrangementBamford-Stevens reaction |
| collection |
DOAJ |
| language |
English |
| format |
Article |
| sources |
DOAJ |
| author |
Marcus Baumann Sophie Lapraille Ian R. Baxendale |
| spellingShingle |
Marcus Baumann Sophie Lapraille Ian R. Baxendale Rac-2′,3a,6,6,6′,6′-Hexamethyl-3a,3b,6,7-tetra-hydrospiro-[benzo[2,3]cyclopropa[1,2-c]pyrazole-1,1′-cyclo-hepta[2,4]diene] Molbank eucarvone dimerization cycloaddition tosylhydrazone 1,3-dipole molecular rearrangement Bamford-Stevens reaction |
| author_facet |
Marcus Baumann Sophie Lapraille Ian R. Baxendale |
| author_sort |
Marcus Baumann |
| title |
Rac-2′,3a,6,6,6′,6′-Hexamethyl-3a,3b,6,7-tetra-hydrospiro-[benzo[2,3]cyclopropa[1,2-c]pyrazole-1,1′-cyclo-hepta[2,4]diene] |
| title_short |
Rac-2′,3a,6,6,6′,6′-Hexamethyl-3a,3b,6,7-tetra-hydrospiro-[benzo[2,3]cyclopropa[1,2-c]pyrazole-1,1′-cyclo-hepta[2,4]diene] |
| title_full |
Rac-2′,3a,6,6,6′,6′-Hexamethyl-3a,3b,6,7-tetra-hydrospiro-[benzo[2,3]cyclopropa[1,2-c]pyrazole-1,1′-cyclo-hepta[2,4]diene] |
| title_fullStr |
Rac-2′,3a,6,6,6′,6′-Hexamethyl-3a,3b,6,7-tetra-hydrospiro-[benzo[2,3]cyclopropa[1,2-c]pyrazole-1,1′-cyclo-hepta[2,4]diene] |
| title_full_unstemmed |
Rac-2′,3a,6,6,6′,6′-Hexamethyl-3a,3b,6,7-tetra-hydrospiro-[benzo[2,3]cyclopropa[1,2-c]pyrazole-1,1′-cyclo-hepta[2,4]diene] |
| title_sort |
rac-2′,3a,6,6,6′,6′-hexamethyl-3a,3b,6,7-tetra-hydrospiro-[benzo[2,3]cyclopropa[1,2-c]pyrazole-1,1′-cyclo-hepta[2,4]diene] |
| publisher |
MDPI AG |
| series |
Molbank |
| issn |
1422-8599 |
| publishDate |
2017-08-01 |
| description |
This note describes a novel reaction cascade in which a tosylhydrazone derivative of eucarvone undergoes a non-classical dimerization process under basic conditions. The key step in this sequence is a dipolar cycloaddition between a diazo species and a transient cyclopropene. A proposed mechanism for this sequence is presented that is supported by single crystal X-ray analysis of the resulting dimer. We believe this unique transformation is of note as it highlights a neat and efficient entry to complex polycyclic architectures containing an embedded pyrazoline moiety. |
| topic |
eucarvone dimerization cycloaddition tosylhydrazone 1,3-dipole molecular rearrangement Bamford-Stevens reaction |
| url |
https://www.mdpi.com/1422-8599/2017/3/M948 |
| work_keys_str_mv |
AT marcusbaumann rac23a6666hexamethyl3a3b67tetrahydrospirobenzo23cyclopropa12cpyrazole11cyclohepta24diene AT sophielapraille rac23a6666hexamethyl3a3b67tetrahydrospirobenzo23cyclopropa12cpyrazole11cyclohepta24diene AT ianrbaxendale rac23a6666hexamethyl3a3b67tetrahydrospirobenzo23cyclopropa12cpyrazole11cyclohepta24diene |
| _version_ |
1725593032888156160 |