Remote stereocontrol using (E)-6-hydroxy-4-methylhex-2-enyl(tri-n-butyl)stannane

Stereoselective Allylstannane Addition for a Convergent Synthesis of a Complex Molecule

“…As reported previously, the stereocenter present in 3 controls the facial selectivity of the transmetalation to give the allyltin trichloride A where the prop-1-en-2-yl and OTIPS groups were in a trans relationship on the six-membered oxastannic ring. It is worthy to mention that these kinds of six-membered oxastannic rings have been widely reported ,, using 6-hydroxystannanes and 6-alkoxystannanes but never using the oxygen of a more oxidated function such as an ester. When aldehyde 2 was added to the reacting mixture it approached this chelated structure to form a new chairlike six-membered transition structure B where the group next to tin adopts the preferred axial position to avoid steric hindrance with the apical chloride on the tin.…”

Update 1 of: Macrolactonizations in the Total Synthesis of Natural Products

“…To date, the Yamaguchi protocol and variations have been used in more than 340 synthetic applications, including eight-membered lactones − such as topsentolide A1 and solandelactone E; − nine-membered halicholactone , and a nine-membered intermediate to laurencin; 10-membered lactones such as didemninlactone, aigialomycin, aspergillides, − aspinolides, , and decarestricine; − exiguolide; , cytotoxic macrolide FD-891; , the bacterial DNA primase inhibitor Sch642305; , iriomoteolide; lituarines B and C; neopeltolide; ,− chloriolide; , oxopolyene macrolide RK-397; , milbemycin; mueggelone; − herbarumin; herbarumin III; , ascidiatrienolide; epothilones A, B, D, E, and F and congeners; ,− lasonolide; macrolactin A; microcarpalide; , erythronolides and analogues; ,,,,,− ,− leiodolide; oleandolide; ,…”

Remote stereocontrol using functionalized allylmetal reagents

“…Transmetallation of the 5‐alkoxy‐4‐methylpent‐2‐enylstannane 14 was stereoselective in favor of the anti ‐allyltin trichloride 15 , which reacted with aldehydes to give the ( Z )‐1,5‐ anti ‐hex‐3‐enols 16 with very high 1,5‐stereocontrol,11 and analogous reactions of the 6‐hydroxy‐4‐ and ‐5‐methylhex‐2‐enylstannanes 17 and 19 with transmetallation using tin(IV) bromide were stereoselective in favor of the 1,5‐ and 1,6‐ anti ‐( Z )‐products 18 and 20 12,13 (see Scheme ).…”