Patent ID: 8906848

Claim:
A method of generating a compound of Formula I wherein one of R 1 , R 2 , R 3 , or R 4 is —X, and the remainder are —H, wherein X is a halogen; comprising: reacting a compound of Formula V with a halogenating reagent in the presence of a first solvent to form the compound of Formula I wherein one of R 5 , R 6 , R 7 , or R 8 is and the remainder are —H; and each of R A and R B are independently —C 1-4 alkyl, —C 3-6 cycloalkyl; or R A and R B together with the oxygen atoms to which they are attached form a 5-6 membered ring optionally substituted with 1-4 of —C 1-3 alkyl, —C 1-3 alkoxycarbonyl, —C 1-3 alkylaminocarbonyl, or any combination thereof; or R A and R B together with the oxygen atoms to which they are attached form a 7-10 membered bicyclic or tricyclic ring optionally substituted with 1-4 of —C 1-3 alkyl, —C 1-3 alkoxycarbonyl, —C 1-3 alkylaminocarbonyl, or any combination thereof.