File:Sherburn's Total Synthesis of (-)-Artigenin.png

Sherburn's Total Synthesis of (-)-Arctigenin

The following synthesis begins at the top left and follows the respective arrows to the bottom left product, (-)-Arctigenin.

(I)The first step involves the formation of the boron enolate of the oxazolidinone [1], which then is reacted with the given aldehyde[2] to produce this first structure [3] in an approximate 92% yield.

(II)In the following two steps the chiral alcohol is protected by the creation of an -OTBS group [4]. After which the oxazolidinone is removed to form a terminal alcohol [5].

(III)Separately the aldehyde [6], is reduced to an alcohol [7], the alcohol is reacted with thiophosgene (CSCl2) to produce a very reactive C-Cl bond in place of the alcohol[8].

(IV)The terminal alcohol from structure [5] reacts with the C-Cl bond from structure [8] to produce a combined product [9]

(V)(add link to radical rxn here)

(VI)

(VII)

(VIII)

InChI

[1]InChI=1/C9H10O3/c1-11-8-4-3-7(6-10)5-9(8)12-2/h3-6H,1-2H3

[2]InChI=1/C14H15NO3/c1-2-6-13(16)15-12(10-18-14(15)17)9-11-7-4-3-5-8-11/h2-8,12H,9-10H2,1H3/b6-2+/t12-/m0/s1

[3]InChI=1/C23H25NO6/c1-4-18(21(25)16-10-11-19(28-2)20(13-16)29-3)22(26)24-17(14-30-23(24)27)12-15-8-6-5-7-9-15/h4-11,13,17-18,21,25H,1,12,14H2,2-3H3/t17-,18-,21+/m0/s1

[4]InChI=1/C26H33NO5Si/c1-7-21(24(33(4,5)6)19-13-14-22(30-2)23(16-19)31-3)25(28)27-20(17-32-26(27)29)15-18-11-9-8-10-12-18/h7-14,16,20-21,24H,1,15,17H2,2-6H3/t20-,21-,24+/m0/s1

[5]InChI=1/C16H26O3Si/c1-7-12(11-17)16(20(4,5)6)13-8-9-14(18-2)15(10-13)19-3/h7-10,12,16-17H,1,11H2,2-6H3/t12-,16+/m1/s1

[6]

[7]

[8]

[9]