Ok, it look's like you have two options
1 the grignar with DMF Just read
Post 191789 (missing)
(element109: "Armchair chemistry: 2C-X 'cursors from hydroquinon", Novel Discourse)2 chloromethylate and then oxidise.
I made some cut and past from the hive
From
Post 275926 (missing)
(starlight: "piperonyl chloride ---> piperonal", Chemistry Discourse)Taken from J. Chem. U.A.R., 11, No. 3, 401-404 (1968):
SYNTHESIS OF 3,4,5-TRIMETHOXYBENZALDEHYDE FROM 3,4,5-TRIMETHOXYBENZYL CHLORIDE
B-Sommelet Method--To a solution of 11 g of hexamethylenetetramine (hexamine) in 70 mL of chloroform was added 18 g (0.07 mole) of IIb (3,4,5-trimethoxybenzyl chloride). The solution was refluxed for 4 hr during which time a precipitate of the quaternary salt was formed. The solvent was removed under reduced pressure and 35 mL of acetone was added. The precipitate was filtered off and heated for 20 min with 100 mL of water. Concentrated hydrochloric acid (17.5 mL) was added and the refluxing was continued for 5 min. After concentration under reduced pressure and cooling the precipitated aldehyde was filtered off. It forms colourless needles from benzene (12 g, 66% yield), mp 72-74 C.
From
Post 228725
(foxy2: "Re: Piperonyl Chloride Question", Methods Discourse)Chloromethylation of 1,3-benzodioxole in the presence of micellar catalysts.
Yingyong Huaxue (2000), 17(5), 563-565.
CODEN: YIHUED ISSN: 1000-0518. Journal written in Chinese.
Abstract
1,3-Benzodioxole was monochloromethylated directly by aq. formaldehyde and hydrogen chloride gas in CCl4 in the presence of quaternary ammonium salts: c16H33(CH3)3NX (X = Br, Cl), C12H25(CH3)3NCl, C12H25(CH3)2(C6H5CH2)NCl and (C4H9)4NBr. With hexadecyltrimethylammonium bromide at temp. 60°-65° for 15 h of reaction, 1,3-benzodioxole was converted to piperonyl chloride with conversion >98% and selectivity up to 97%. The method has advantages of high selectivity, high conversion, negligible byproducts and easy workup of the mail product.
Flavoring materials contain the title compd. (I). I, which has strong and continuous floral fragrance, is stable and useful for various uses, e. g. cosmetics, hair prepns., soaps, detergents, drugs, etc. Treatment of 366 g methylenedioxybenzene with 99 g paraformaldehyde in MePh with feeding HCl at 25-35° for 4 h gave 423.6 g crude 3,4-methylenedioxybenzyl chloride
Hope that help's