SRN1 reactions of 7-iodobicyclo[4.1.0]heptane with carbanions. A novel stereoselective CC bond formation on cyclopropane rings
✍ Scribed by Mónica A. Nazareno; Roberto A. Rossi
- Publisher
- Elsevier Science
- Year
- 1994
- Tongue
- French
- Weight
- 553 KB
- Volume
- 50
- Category
- Article
- ISSN
- 0040-4020
No coin nor oath required. For personal study only.
✦ Synopsis
The plWhmulated xeaction of 7-iodobicyclo[4.1.0]-heptane (7-iodooorcarane, 1, a mixture of cu. 1: 1 of the exo:endo isomers ) with acetoplmone. molate ion 2 io DMSO at 60°C gave the substitim products 3a (em) aud 3b (en&) in 87% yield (with an exo:endo ratio of 16). III the dark at 6o"c, not only thcipso~produds38aad3b(5l%),butalsotbecinesubetiMionproduct4mrefamd(2o%) byaneliminat~-addition~~InthcdarkandatroomtcmpcraturcthcrcisnorcactionItissuggtsted tbatl~~Zbyaphotostimulstadaswellasathcrmal(60"C)~lrtactiontogivetheipsoproducts 3,witha3a:3bratioofca. l5-~,showinga~~ofthe7-mrcllranyl~inthecoupling ~~2.M~adcctivityof1with2wasformdinthephotostimulatednactioninliquid~(at -33Q with a 3a:3b ratio of cu. 55, although iu lower yields (3Ph). The pimkh&&d MC&II of 1 with 2-acetonapMbone7gave~thelppopTodllcts(with811exo:endoratioof45)andindarkcmditioosat6ooC tbeieisnoreactionwith7.Thacwasnophotostimulatcdnsctionof1withthcanionof~~9ia DMSO.However,thephotostimulatcdreactionoflwith9inprescmxof~~~i~lO,theipso sllbamapoduds daived fhm 9 were fovmad (allrd S,l reactioo), with an exo:endo ratio of cu. 7.3. From competition experiments, 9wascu. 6.4timesmmreachvethau2.