2.2- Dibutyl-2-stanna-1,3-dithiane

Dibutyl-2-stanna-1,3-dithiane, Bu2Sn(OTf)2, CICH2CH2CI, 35°, 1 h, 77-94% yield. TBDMS, TBDPS, THP, and OAc groups are not affected by these conditions. 

Since the formation of Sn-S bonds is kinetically and thermodynamically favorable 2-stanna-l,3-dithiolanes or—dithianes are easy to prepare, for instance from dibutyl tin dimethoxide or from dibutyltin oxide (see Formula 9.4, bottom). 

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