Science of Synthesis

Wicha, J., Science of Synthesis, (2009) 48, 190.

The free-radical chain reaction of xanthates (dithiocarbonate O,S-esters) with tributyltin hydride, first reported by Barton and McCombie,[‌125‌] provided a basis for the most versatile and reliable method for deoxygenation of secondary alcohols, which is also applicable to primary and tertiary alcohols in certain cases. Various aspects of the Barton–McCombie reaction have been reviewed.[‌3‌–‌5‌,‌7‌,‌126‌,‌127‌] Although the invention of this deoxygenation method was stimulated by the need for an efficient synthetic approach to deoxysugars that could be used to modify aminoglycoside antibiotics,[‌128‌,‌129‌] the first experiments were performed on monofunctional sterols.

Meeeeeeee ee eee M-eeeeee eeeeeeee ee eeeeeeeeeee (‌88‌) eeee eeeeeeeeeee eeeeeee ee eeeeeeeee eeeeeee eeeee eeeeeeee eeeee eeeeeee-8-eee (‌88‌) ee 88% eeeee (‌Meeeee 88‌). Meeeeeee eeeeeee eee eeeeeeee(eeeeeeeeeeeeee)eeeeeeee eee eee eeeee eeeeeeee eeeeeeee. Mee eeeeeeeeeeee M-eeeeee eeeeeeee eee ee eeee eeeeeeee ee eee eeeeeeeee eeee eeeeeee eeeeeeeee. M eeeeeeee ee eee eeeeeeee ee eeeeeee ee eeeeeeee eeeee ee e eeeeeeee ee eeeeeeeeeee eeeeeee ee eeeeeeeee eeeeeee, eeeeeeee eee eeeee ee eeeeeeee ee eee eeeeeeee eeee eee eeeeeee eeeeee eee eeeeeee ee eee eeeeeeee.

‌Meeeee 88‌ Meeeee–MeMeeeee Meeeeeeeeeeee ee Meeeeeeeeee[‌888‌]

Mee Meeeee–MeMeeeee eeeeeeeeeeeee eeeeeeee eeeeeeee eee eeeeeeee eeeeee: eeeeeeeeeeeeee ee eee eeeeeee eeee e eeeeeeeeeeee eeeeeeeeee, eee eeeeeeeee ee eee eeeeeeeeeeee eeeeeeeeee eeee eeeeeeeeeee eeeeeee. Mee eeeeeeeee ee eeeeeee eee ee 88–888°M eeee eee eeeeeeeee ee eeeeeeeeeee eeeeee. Meeee eeeee eeeeeeeeee, eeee ee eee eeeeeeeeeee eeeeeee eeee ee eeeeeee eeeeeeeee eeeeeee eeeeeeeeeeee ee eeee eeeeeeeeeeeeeee eeeeeeee eeee eee ee eeeee eeeeeeeeeee.[‌888‌–‌888‌] Meee eeeeeeeee eeeeeee ee eee Me—M eeee ee eeeeeeeeeee eeeeeee eee eeee ee eeeeeeee eeeeeeeeeeeeeee ee eeeeeeeee eeeeeeeeee ee eeeeeeee eeeeeee ee eee eeeeeeee eeeeee. Meee-eeeeeee eeeeeeeeee, eeee ee 8,8′-eeeeeeeeeeeeeeeeeeeeee, eeeeeeeeee eeeeeeeee ee eee eeeeeeeeeeee eeeeeee.[‌888‌–‌888‌] Meee 8,8′-eeeeeeeeeeeeeeeeeeeeee (8.8 eeeeeeeeeee) ee eee eeeeeeeee, eeeeeeeee eee eeeeeee eee eeeee 8.8 eeeeeeeeeee ee eeeeeeeeeee eeeeeee. Meeee eeeeeeeeeeee ee eee eeeee eeeeeeee eee eeeee ee eeeeeee eeeeee, ee ee eeeeeeeee ee eeeeee eeee eee eeeeeeeee ee eeeeeee eee eee eeeeee eeeeeeee ee eee eeeeeeee; eeee eee ee eeeeeeee ee eeeeeeeeeee eeeeeeee ee eee eeeeeeeee ee, eeeeee eeeee, eeeeeeeeee eeeeeeee ee e eeeeeeee ee eee eeeeeeeee ee eeeee ee e eeeeeee eeee.[‌888‌]

Mee eeeeeeeee ee eee Meeeee–MeMeeeee eeeeeeee ee eeeee ee ‌Meeeee 88‌.[‌888‌,‌888‌]

‌Meeeee 88‌ Mee Meeeeeeee ee eee Meeeee–MeMeeeee Meeeeeee[‌888‌,‌888‌]

Mee eeeeeeeeeeeeeee eeeeeee eeee ee eee eeeeeeeeeeee eeeee ee eee M-eeeeee eeeeeeee ee eeee ee eeeeeeeeeeee eeeeee-eeeeeeee eeeeeee ‌88‌; eeee eeee ee eeeee eee eeeeeeeeee.[‌888‌] Mee eeeeeee ‌88‌ eeee eeeeeeeee eeee e eeeeeee ee eee M—M eeee ee eeeeeeee e eee eeeeeee ‌88‌, eeeee eeeeeeeee e eeeeeeee eeee eeee eeeeeeeeeee eeeeeee ee eeeeeee eee eeeeeee eee ee eeeeeeeeee eee eeeeeeeeeeeeeee eeeeeee. M eeeeeee eeeeeee eeeeeeeeee ee eee eeeeeee eeeeeeeeeeeee ‌88‌ eee ‌88‌, eee eeee ee eee eee eeeeeee ee eeeeeee eee eee eeeeeeee eeeeeee. Me ee eeeeeeeeeee eeeeeeeeeee (eeeeeee 88–888°M) eee e eee eeeeeeeeeee eeeeeee eeeeeeeeeeeee (eeeeeee <8.8 M), eeeeeeeeeeeee ee ‌88‌ eeeeee ee eee eeee eeeeeee; eeeeeee, eeeeeee ‌88‌ eee eeee ee eeeeeee ee eeeeeeeeeee eeeeeee. Meee eeee eeeeeeee eeeeeeeeee eeeee ee e eeeeeee eeeeeeeeee ‌88‌ eee ee eeee eeeeeeeeeee eee eeeeeeeeeeee ee eee eeeeee eeeeeee (‌Meeeee 88‌). Meeee eee eeeeee eeeeeee eeee eeeeee eee eeeeee ee eee eeeeeeee ee eeee eeeeee.[‌888‌–‌888‌]

‌Meeeee 88‌ Meeee Meee Meeeeeeee ee eee Meeeee–MeMeeeee Meeeeeeeeeeee

Mee eeee eeeeeeeee eeeeeeeeee ee eee Meeeee–MeMeeeee eeeeeeee, eeeeeeee eeee eeeee eeeeeee eee eeeeeeeeeeeee ee eeeeeeeee eeeeeeee, eee e eee eeeeeeeeeee ee eeeeee eeeeeeeee ee eee eeeeeee eeeee eee e eeee eeeeee ee eeeeeeeeeeeeeeee. Meeeeeee eeeeee ee eeeeeeeee, eeeeeee, ee eeeeee eee eeeeeee eeeeeeeeee ee eee eeeeeeee eeeeeeeeee. Meee eeeeeeeeeeee, eeeeee-eeeeeeeeee eeeeeeeeeeee, eee eeeee eeeeee eee eeee ee eeeeeeeee ee eeee eeeee. Meeeeeee eeeeeeeee eeeeeeeeeeeeeeee eeeeeeeee eee ee eeeeeee eeeeeeeeeee ee eee ee eee eeeeeee eeeeee eee ee eeeeeeeee eeeeeeeeeee eeee e eeeeeeee eeeeeeeeeeee eeeeeeeeee. Mee eeeeee ee eeee eeeeee eee eeeeeeeee ee α-eeeeeee eeeeeee, α-eeeeeee eeeeee, ee α-eeeeeee eeeeeeeeeeee. Meee e eeeeee ee eeeeee eeee ee eeeeeee ee eee eeeeeee, eee eeeeeeeeeeee eeeeeee eee eeeeeee, ee eeeeeeeee ee eee eeeeee eeee eeeeeeeeeeeee eee eeeee. Meeeeeeeeee, eee eeeeeeee ee eeeeeeee eeeeeee eee eeeee eeeeeee eeeeeeeeee, ee eeee eeee- ee eeee-eeeeeeeee eeeeee eee eeeeee eeeeeee ee eee eeeeeeee α ee eeeeeeee-eeeeeeeeeee eeeeee eee eeeeeee eeeeeeeeee.

Mee Meeeee–MeMeeeee eeeeeeee ee eeeee eeeeeeeeee eeee ee eeeeeeeee eeeeeeee. Meeeeeee eeeeeee eeeeeeee eeeeeee eeee eeeeeeeee eee eeeeeee eeeeeeeeeeee eeeeeeeeeee, eee eeeeeeee ee eeeee eeeeeeeeeee eeee eeeeeeeeeee eeeeeee eeeeeeee eeee-eeeeeee eeeeeeeeee ee eeee eee eeee eeeeee eeeeeeeeeeee eeeeeee eeeeeee (eeeeeee 888–888°M). Meeee eeeee eeeeeeeeee, eeeeeeeee eeee e eeeeeeee eeee ee eee β eeeeeeee eee eeeeeee eeeeeeeeeeeee eeeeeeeeeee (eee Meeeeee eeeeeeeeeee).[‌888‌] Me eee eeeee eeee, eeeeeeee eeeeeeee eeeeeee eeeeeee eeeeeeeeee ee eee eeeeeeeeeeeeee eeee, eee eeeeeeeeeee eeeeeeeeee eeeeee eeeee eee eeeeeeeeee eeeeeeee eee eee eeeeeeeee ee eee eeeeeeee. Me eeeeeeee, eeeeeeee-eeeeeee-eeeeeee eeeeeeeee, ee eeeeee, eeeeeee eeee-eeeeeee eeeeeeeee eeeee eeeeeeeeee eeee eeeeeeeeee.

Mee eee ee eeeee eeeeeeeeeee eeeeeee ee eee eeeeeeeee eeee ee eeeeeeeeee eeee eeeeeeeeeeee eeeeee eee eeeeeeeeeeeee eeeeeee, eee eee eeeeeee ee eee-eeeeeeeeee eeeeeeeeee eeee eee eeeeeeee ee eeeeeee eeee eeeeeeeeee eeeee eee ee ee eeeeeeeee. Meeeeee eeeeeeeeeeee eeeeeeeeee eee eeeeeeeee. M eeeeeee eeeeee eeeeeeee eeeeee eeee eeeeeee eeeeeeeee eeeeeeee[‌888‌–‌888‌] ee eeee eeeeeeeee eeeeeeeee eeee eee eeeeeeeeeee eee eeeeeeeee (ee eeeeeee eeeeeeee ee eeeee) eeeeeeeee eeeeeeeee eeee eee ee eeeeeee ee eeeeeeeeee eeeeeeeee ee ee eeeeeeeeeeeeee. Meeeeeeeeeeee, e eeeeeee ee eeeeee eee eee eeeeee eeeeee eeeeeeeee eeeeeeee eee ee eeee ee e eeeeeeeeee eeeee ee eeeeee eeeeeeeeeeeeee.[‌888‌] M eeeeeeeeee eeeeeeeee eee eeeeeee ee eeeeeeee eeeee eeee eeeeeee eeeeeeeee eeeeeeee eee eee ee eeeee eeeeee eeeeeeee/eeeeee eeeeeeeee eeeeeeee.[‌888‌] Me e eeeeee eeeeee eee eee eeeeeeeeeeee ee eeeee eeeeeeeee, eee eeeee eeeeeee ee eeeeeeeeeee eeeeeee eeeeeeeeeeee (eeeee eeeeeeeeeeeeee eeeeeeeee eee eeeeeee eeeeeeeee) eee eeeeee (eeeee eeeeeeeee eee eeeeeeeeeee eeeeeee).[‌888‌] Me eee eeee eeee eeeeeeee eeee eeeeeeeee ee ee eeeeeeee eeeeeeee ee e eeeee eeeeeeeee eeeeeee eeee e eeeeee eeeeee ee 8,8-eeeeeeeeeeee[8.8.8]eeeee-8-eee eeeeeeee ee eeeeeeeee eeee e eeeeeeee ee eeeeee ee eeeeeee eeeee eee eeeeeeeeee eeeeeee e eeeeee eee eeeeee eeeeeee eee-eeeeeeeeee eeeeeeeeee.[‌888‌] Meeeeee eeeeee eeeeeeee eeeeeeee ee eeeeee eeeeeeeeeeeeeeee eee eeee-eeeee eeeeeee ee eee eeeeeeee eeeeeee eeeee eeeeeeeeee ee eee eeeeeee eeeeeeee, eeeeeeee ee eeeee eeeeeee eee eeeeeeeeeeeeeee eeeeeeeeee, eeeee eeeeeee eee eeeeeeee ee eeeeeeee eeeeeeeeeee eeeeeee.[‌888‌]

Meeeeee eeeeeeeeeeeee ee eee eeeeeeee Meeeee–MeMeeeee eeeeeeeee eee eeeeeeeee eeee eeeeeee eeeeeeeee ee eee eeeeeee eeeeee ee eee eeeeeeeeeeeee eeeeeee. Meeeeeee eee eeeeeeee ee eee eeeeeeeee ee e eeeeeeee eeeeeee, eeeeeeeeeee eeeeeee eeeeeee eee eeee eeeeeee eeeeee ee eeeeeeee eeeee. Meee eeeee eeeee eeeeeeee, eeeeeee, eeeeeeeeee-eeeee eeeeeeeeee, eeeeeee eeeeee, eeeeee-8-ee, ee eeeee eee eeee eeeee ee eeeeeeee eeeeee.

M eeeee ee eeeeeee eeeeeeeeee eee ee eeee ee eeeeeee eeeeeeeeeeeee eeeeeeeeee, eeeeeeeee ee eeeeeee eeee ee eee eeeeeeee eeeeeeeeeee ee eee eeeeee;[‌888‌,‌888‌] eeee eeeeeee eee eeeee eeeee. Mee eeeeeeeee eeeeee ee eeeeee ee eeee ee eee e eeeeeeee eeee-eeee ee eee eeeeeeee eeeeeeeeeee. Meee eeeeee eeee-eeeeeee eeeeeeeeee eee eeeeee ee ‌Meeee 8‌; eeeeeeeeeeee ee eeeee eeeee eeee-eeeee eee eeeeeeeeeeeee 8 eeee eee eeee eeeeee, ee eeeeeeee.[‌888‌,‌888‌] Meeeeee eeeee eeeeeeeeee eee eee eeeeeeeeeeeee eeeeeeee eee eeee eeeeeeeee.[‌888‌,‌888‌]

‌Meeee 8‌ Meee-Meeeeee Meeeeeeeee eee eee Meeeee–MeMeeeee Meeeeeee[‌888‌,‌888‌,‌888‌–‌888‌]

e Meeeeeeeeee eeeeeeeeeee ee eeeee eee eeeeeeeee eeeeeeeeeeeee eeee eeee ee 8 e.

Me-eeee-eeeee eeeeeeeeeeeeeeeee eee ee eeee eeee eeeeeeeeeee eeeeeee ee eeeeee eeeeeeeeeeeee ee eeeeeeeee eeeeeeee ee eeee eeeeeeeeeee ee eeeeeee eeeeeeee.[‌888‌,‌888‌]

8,8′-Meeeeeeeeeeeeeeeeeeeee ee eee eeeeeee eeeeeeeee eeee ee eeee eeeeeeee eeee ee eeeeeeeeee eeeeeeee. 8,8′-Meeeee(eeeeeeeeeeeeeeeeeeeeeee) eee 8,8′-eeeeee(8-eeeeeeeeeeeeee eeee) eeee eeee eeeeeeee ee eeeeeeeeee eee eee eeeeeeeee eeeeeeeeeeeee ee eeeeee eeeee eeeeeeeeeeee eeeeeeeeeee.[‌888‌] 8,8′-Meeeee(8-eeeeeeeeeeeeee eeee) ee e eeeeeeeeee eeeeeeeeeee ee 8,8′-eeeeeeeeeeeeeeeeeeeeee, eee eeeeeeeeee eee e eeeeee eeeeeee eeeeeeeee; ee ee eeee eeeeeee ee eeeeee eeeeeeee, eeee ee 8-eeeeeeeeeeeeee.

Meeeeeeee eeeeeeee ee eee eeee-eeeee eeeeeeeeee eeeeeee eeeeeeeee. Meeeeeeee eeeeeeee ee e eeeeeeeeee eeeeeeeeeee ee eeee ee ee eeeeeeeeeee eee eeeeeeeeee ee eeeeeee eeeeeeeee eeeeeeeeee. eeee-Meeee eeeeeeeeeeeeee eee ee-eeee-eeeee eeeeeeee eee ee eeee eee eeeeeeeee eeee e eeee eeeee ee eeeeeeeeeeee.

Meeeeeeeeeee ee eeeeeeeeeeeeeee eeeeeeee e eeeeeeee eeee-eeeeeee-eeeeeeeeee eeeeeeeee (‌Meeeee 88‌). Meeeeeeeeeeee ee M-eeeeee eeeeeeeee ee eeeeeee eeeeeeeee eeeeeeee eeee eeeeeeeeeee eeeeeee (8.8 eeeeeeeeeee) eee ee eeeeeee eee eeeeeeeeeee ee eeee eeeeeeeeeee ee eeeee (eeee ee −88°M) eeeee eeeeeeeeeeeeee eee eeeeee eeeeee.[‌888‌,‌888‌]

‌Meeeee 88‌ Meeeeeeeeeeeee/Meeeee-Meeeeee Meeeeeeeee ee Meeeeeeeeeeeeee Meeeeeee

Meeeeeeee eeeeeee ee eeeeeeeeeeeeee eee eeeeeeeeeeeeeee eee eeeeeeee eeee. Me ee eeeeeeeeeee eeee e eeeeeeee eeeeee ee eee eee eeeeeeeeeeeee ee 8 eeeeeeeeee ee M8 ee eeeeeeeeee eeeeeeeeeee ee eeeeeeeeeeee (ee eeeee ee e eeeeeee eeee) eeee eee eeeeeeee eeeee, eeeee ee eeeeee eeee eee eeeee;[‌888‌] eeeeeee, eeeeeeeeee eeeee ee eee eeeeeee eee eeeeee, eeeeeeeee ee eee eeee eee eeeee eeeeeee, ee eeeeeeee eee ee eee eeeeeeee eeeeee eee eeeeeee eeeeeeeeee eeeeee ee eeeeeeee eee eeeeeeee. Meeeeeeeeeee eeeeeee eee ee eeeeeeee eeee ee eeeee eeeeeee eeeeeeee eeeeee eeeee eeeeeeee eeeeeeeeee eeeeeeeeee; eeeeeeeeee eeeeeeee eee eeee eeeeeeeeeeee.[‌888‌]

Mee eeeeee/eeeeee eeeeeeeee ee eeee eeeeee ee eeeeeeeeeeeee eeeeeeeee eeee eeee eeeeee eee-eeee eeeeeeee-eeee eeeeee, eeee ee eeeeeee (eee eeee Meeeeee ‌88.8.8.8.8‌). Meee eeee eeeeeeeeee eeeeeeeeeeeee ee eeeeeeeee (88%) eeeeee ee eeeeeeeeeeeeee/eeeeeeee-eeeeeeeee eeeeeeeeeeeee ee M-(8-eeeeeeeeeeee) M-(8-eeeeeeeeeeee-8-ee) eeeeeeeeeeeeee eeee eeeeeeeeeeeeeeeeeeeeee;[‌888‌] eeee eee ee eee eeeeee ee eeeeeeee ee β-eeeeeeee eeeee eeee eee eeeee eeeeeee.

Meeeeee eeeeeeeeeeee eeeeeeeeeee eee eeeee ee eeeeeeeeeeee eeeeee ee eee Meeeee–MeMeeeee eeeeeeee. Me eeeeeeee ee eeee eeeeeeee eeee eee ee eeee eee eeeeeeeeeee ee eeeeeeeeeeee eeeeeeeeeee ee eeeeeeeee ee ‌Meeee 8‌.

‌Meeee 8‌ Meee Meeeeeee eee eee Meeeeeeeeee ee Meeeeeeeeeee Meeeeeeeeee eee eee Meeeee–MeMeeeee Meeeeeee[‌888‌,‌888‌–‌888‌,‌888‌,‌888‌–‌888‌]

e MMMM = 8,8′-eeeeeeeeeeeeeeeeeeeeeee.

e Meeeee eeee eeeeeeeeeeeeeee.

References

Meeeeee Meeeeeeeeee

• 8.Meeeee-Meee, (8888) 88/8e, 888.