Synthesis of spirocycles via ring closing metathesis of heterocycles carrying gem-diallyl substituents obtained via ring opening of (halomethyl)cyclopropanes with allyltributyltin.
In the presence of allyl tri-n-butyltin--AIBN, cyclopropylmethyl bromides/xanthates undergo ring-opening reaction with concomitant formation of geminal diallyl derivatives in good yields. The ring closing metathesis reactions on geminal diallyl derivatives with Grubbs' catalyst provided spirocyclopentenyl products. Combination of these two methodologies has been applied to the synthesis of mono-, bis-cyclopentyl-carbohydrates as well as spirocyclopentylproline derivatives.
Gurjar
Mukund K
MK
National Chemical Laboratory, Pune, 411 008, India.
Ravindranadh
Somu V
SV
Sankar
Kuppusamy
K
Karmakar
Sukhen
S
Cherian
Joseph
J
Chorghade
Mukund S
MS
D003521:Cyclopropanes / Q000737:chemistry*; D006571:Heterocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D013057:Spectrum Analysis; D014220:Trialkyltin Compounds / Q000737:chemistry*
D003521:Cyclopropanes; D006571:Heterocyclic Compounds; D014220:Trialkyltin Compounds; C011559:tributyltin