Tools
Tools
Hale, KLE, Fielding, AJ and Hale, KJ (2025) On the divergent reactivity of allenylstannanes generated from the O-directed free radical hydrostannation reaction of (±)-trans-3-(2-phenylcyclopropyl)prop-2-yn-1-ol. EPR evidence for the reversible addition of Ph3Sn radicals to vinyl triphenyltins. Organic & Biomolecular Chemistry. ISSN 1477-0520
|
Text
d4ob01847h.pdf - Published Version Available under License Creative Commons Attribution. Download (2MB) | Preview |
Abstract
(±)-trans-3-(2-Phenylcyclopropyl)prop-2-yn-1-ol (5) undergoes O-directed rt free radical hydrostannation with 2 equiv. of Bu3SnH or Ph3SnH in PhMe to produce the α-cyclopropyl-β-stannylvinyl radicals 26 and 27, which rapidly ring-open to give the benzylic stannylhomoallenyl radicals 28 and 29. These, in turn, react with the excess stannane that is present to provide 21 and 23 as primary reaction products. The triphenylstannylallene 23 also undergoes a competitive Ph3Sn˙ addition to its central allene carbon. This affords the allylically-stabilised radical 31c, which itself reacts with the stannane to produce (Z)-6-phenyl-2,3-bis(triphenylstannyl)hex-3-en-1-ol (24). EPR studies of the reaction of 5 with Ph3SnH (1 equiv.) and cat. Et3B/O2 in PhMe at 250 K have failed to identify the radicals 27 and 29 in the reaction mixtures. Rather, a sharp dd is always observed whose multiplicity is consistent with it being the tris-Ph3Sn-stabilised free radical 33. The latter is suggested to arise from a reversible O-directed Ph3Sn˙ addition to 24. The radical 33 has 1Hβ values of 1.32 mT (13.2 G) and 0.57 mT (5.7 G) and a g of 2.0020.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | 3402 Inorganic Chemistry; 3405 Organic Chemistry; 34 Chemical Sciences; 0304 Medicinal and Biomolecular Chemistry; 0305 Organic Chemistry; Organic Chemistry; 3404 Medicinal and biomolecular chemistry; 3405 Organic chemistry |
| Subjects: | Q Science > QD Chemistry Q Science > QH Natural history > QH301 Biology |
| Divisions: | Pharmacy and Biomolecular Sciences |
| Publisher: | Royal Society of Chemistry (RSC) |
| SWORD Depositor: | A Symplectic |
| Date Deposited: | 08 Apr 2025 13:46 |
| Last Modified: | 08 Apr 2025 13:46 |
| DOI or ID number: | 10.1039/d4ob01847h |
| URI: | https://researchonline.ljmu.ac.uk/id/eprint/26122 |
 |
View Item |