| 主权项 |
1. A method of synthesizing a compound of formula (I): wherein: X is selected from the group consisting of O and NR1; R1 is selected from the group consisting of hydrogen, alkyl, and a nitrogen protecting group; R2 is selected from the group consisting of —C(O)O—, —C(O)—, —O—, —NR4— and —CR52—; each R3 is independently selected from the group consisting of hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclyl, aryl, heteroaryl and cyano, any of which may be optionally substituted; R4 is selected from the group consisting of hydrogen, alkyl, and a nitrogen protecting group; and each R5 is independently selected from the group consisting of hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclyl, aryl, heteroaryl, acyl, alkoxy, amido, amino, carboxy, cyano, ester, halo, haloalkyl, hydroxy, nitro, phosphonate, sulfinyl, sulfonyl, sulfonate, sulfonamino and sulfonamido, any of which may be optionally substituted; or two R5 are taken together with the atom to which they are attached to form an optionally substituted ring system; the method comprising combining the following components to form a reaction mixture: a) a compound of formula (II): b) a compound of formula (III): c) a nickel-containing compound; and d) a ligand. |
