Patent ID: 7982051

Claim:
A method for the preparation of a compound of the formula (3a): wherein R 1 is H, or C1-C8 alkyl, C2-C8 alkenyl, C2-C8 alkynyl, C5-C6 aryl, C6-C12 arylalkyl, or a heteroform of one of these, each of which may be optionally substituted; each R 2 is independently H, or C1-C8 alkyl, C1-C8 heteroalkyl, C6-C14 arylalkyl, C6-C14 heteroarylalkyl, optionally fluorinated C1-C6 acyl, C6-C12 aroyl, arylsulfonyl, trialkylsilyl, or alkoxycarbonyl, each of which may be optionally substituted; R 6 is H, or C1-C8 alkyl, C1-C8 heteroalkyl, C6-C14 arylalkyl, C6-C14 heteroarylalkyl, optionally fluorinated C1-C6 acyl, C6-C12 aroyl, arylsulfonyl, trialkylsilyl, or alkoxycarbonyl, each of which may be optionally substituted; and Y is H, or halo, —OH, or —OR 10 , where R 10 is optionally fluorinated C1-C4 alkyl, C2-C4 alkenyl, C6-C14 arylalkyl, optionally fluorinated alkylsulfonyl, arylsulfonyl, optionally fluorinated C1-C6 acyl, or C6-C10 aroyl, each of which may be optionally substituted; said method comprising the steps of: (a) contacting a compound of formula (2a): with an indole of the formula: optionally in the presence of a protic acid, to provide a mixture; wherein R 1 , R 2 , R 6 , and Y are as defined for formula (3a); (b) adding an activating reagent to said mixture; and (c) optionally heating said mixture to provide the compound of formula (3a).