Intramolecular Cascade Lactone Cyclization of Dicoumarol Derivatives Promoted by Tributyltin Chloride

Title:Intramolecular Cascade Lactone Cyclization of Dicoumarol Derivatives Promoted by Tributyltin Chloride

Volume: 11 Issue: 3

Author(s): Sadia Rehman, Muhammad Ikram and Fazle Subhan

Affiliation:

Keywords: Sn(n-Bu)₃Cl, dicoumarol, intramolecular cyclization, single crystal study, lactone.

Abstract: Dicoumarols, derived from aldehydes with ortho hydroxy substitution (5 and 7), were successfully cyclized by Sn(n-Bu)₃Cl in THF as a reaction medium. Catalytic cycle reveals the formation of HO-Sn-O=C cyclic intermediate which is rearranged and isomerized to the cyclic lactone. N-butane was released by Sn(n-Bu)₃Cl leaving behind Sn(n- Bu)₂(OH)Cl keeping the catalytic route continued unless the two butane attached to tin were also consumed. The products produced were characterized using ¹H, ¹³C{¹H}-NMR, high resolution EI-MS, IR and elemental analyses. Single crystals of 6 were grown in P₁ space group from concentration in THF and structurally studied using X-ray diffraction analysis. All the spectroscopic and analytical studies supported the formation of the cyclized products.

Cite this article as:

Rehman Sadia, Ikram Muhammad and Subhan Fazle, Intramolecular Cascade Lactone Cyclization of Dicoumarol Derivatives Promoted by Tributyltin Chloride, Letters in Organic Chemistry 2014; 11 (3) . https://dx.doi.org/10.2174/1570178610666131210233841