Table 1.

Synthesis of chlorinated derivatives of 3,4-dimethoxy-1-methyl-9H-xanthen-9-one (6).

Comp.	R1	R2	R3	Method	Yield (%)
8	CH2Cl	H	OCH3	A B	5 6
9	CH3	H	OH	A B	2 4
10	CH3	H	Cl	A B	12 12
11	CH3	Cl	OCH3	C	26

Method A: SOCl₂, r.t., seven days; Method B: SOCl₂, 40 °C, seven days; Method C: NaCl, p-TsOH, NCS, H₂O, r.t., seven days.