05-07-03 19:52
No 432022
ok .. so heres the references...
1,3-Benzodioxoles from pyrocatechols. Takeuchi, Junji; Enomiya, Takuji; Nakamura, Takato. (Ube Industries, Ltd., Japan). Jpn. Kokai Tokkyo Koho
(1976), 4 pp. CODEN: JKXXAF JP 51100078 19760903 Showa. Patent written in Japanese. Application: JP 75-23907 19750228. CAN 86:140021
AN 1977:140021 CAPLUS
Patent Family Information
Patent No. Kind Date Application No. Date
JP 51100078 A2 19760903 JP 1975-23907 19
Priority Application Information
JP 1975-23907 19750228
Abstract
1,3-Benzodioxoles I (R = CHO, allyl) were prepd. by cyclizing pyrocatechols II with methylene halides and aq. caustic alkali in a polar aprotic solvent while
removing H2O as an azeotrope with the halide. Thus, 0.4 mole II (R = CHO) in Me2SO and 0.93 mole 45.7% aq. NaOH were added to 0.7 mole CH2Cl2 in Me2SO at
reflux over 160 min with azeotropic removal of 42.5 ml H2O. The mixt. was refluxed for 1 h with an addnl. 0.05 mole NaOH and 0.16 mole CH2Cl2 to give 89.7% I (R = CHO), vs. 75% without H2O removal. Similarly, safrole was prepd. in 70.6% yield.
Aromatic alkylenedioxy compounds. Fujita, Harushige; Yamashita, Masataro.
(Japan). Jpn. Kokai Tokkyo Koho (1976), 10 pp. CODEN: JKXXAF JP
51019772 19760217 Showa. Patent written in Japanese. Application: JP
74-89985 19740806. CAN 85:46191 AN 1976:446191 CAPLUS
Patent Family Information
Patent No. Kind Date Application No. Date
JP 51019772 A2 19760217 JP 1974-89985 19
Priority Application Information
JP 1974-89985 19740806
Abstract
1,2-(Alkylenedioxy)benzene derivs. I (R1 through R4 = H, halo, lower alkanoyl, alkenyloxy, alkyl, alkenyl, lower alkoxy, NO2, CHO; one of them may be either OH
or Q; 2 adjacent groups be form an alkylenedioxy group; n = 1-6) were prepd. by gradual reaction of 1,2-dihydroxybenzenes II (R5 through R8 = H, halo, lower
alkanoyl, alkenyloxy, alkyl, alkenyl, lower alkoxy, NO2, CHO; one of them may be OH; 2 adjacent groups may form an alkylenedioxy group) with R(CH2)nR (R = halo,
HOSO3) in polar aprotic solvents. I are useful as perfumes and insecticides (no data). Thus, 110 g catechol and 100 g KOH were added to 200 g CH2I2 in DMF over 140-60 min at 110-40* under N, 50 g CH2I2 was added, and the mixt. stirred 30 min to give 80% 1,2-(methylenedioxy)benzene. Among 27 addnl. I prepd. were bis(2,3-methylenedioxyphenoxy)methane, 2,3-(methylenedioxy)anisole, 1,2-dimethoxy-4,5-(methylenedioxy)benzen
Synthesis of the dihydroxyphenyl (X) from vanillin and Eugenol are not described.... luckily i have the (dihydroxyphenol) aldehyde :D [joy] (have sourced a few methods for demethylation from scifinder.. but havent tried them as yet... soon.. hopefully) ...
i will attempt to prepare piperonal from dimethoxybenzaldehyde this weekend... but i welcome others to try as well.... i dont have any of the dimethoxyphenylalkene ... but i will sourse some preps for that and attempt some safrole preps from Eugenol
as well.... again.. others feel free to attempt these :D
..
your thoughts on these rxns and workup will be nice
regards..
(Hive Bee)
05-08-03 02:45
No 432097
will attempt to prepare piperonal from dimethoxybenzaldehyde this weekend...
you need a di-hydroxy substituted derivative, not a di-methoxy substituted.
(Stranger)
05-08-03 04:09
No 432117
hehehe.. typo... meant to say will attempt robust prep of piperonal by methylenation of dihydroxyphenylaldehyde.. :D .... my bad :D ....
there are loads of methylenation routes... however im yet to find a convenent route to piperonal or safrole that uses chemicals with lowish toxicity ... but ive dug up a couple this week so i hope get the rxns done this weekend... thankx for that correction