Compound(3400-55-3)Synthetic Route of C7H15BrO2 received a lot of attention, and I have introduced some compounds in other articles, similar to this compound(2-Bromopriopionaldehydediethylacetal), if you are interested, you can check out my other related articles.
The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Ketene acetals. XXXIII. The addition of halogens and cyanogen compounds to methylketene diethyl acetal》. Authors are McElvain, S. M.; McLeish, Wm. L..The article about the compound:2-Bromopriopionaldehydediethylacetalcas:3400-55-3,SMILESS:CC(Br)C(OCC)OCC).Synthetic Route of C7H15BrO2. Through the article, more information about this compound (cas:3400-55-3) is conveyed.
cf. C.A. 49, 14687i. Salts of the type [MeCHXC(OEt)2]Xn-1 (n = 4 when X = iodine; n = 0 and 2 when X = Br) have been isolated and shown to be the intermediates through which certain dimeric products are formed when these halogens react with MeCH:C(OEt)2 (I). (CN)2 did not react with I, but both BrCN and ICN add readily to give only MeCHXC(OEt)2CN in high yields. HCN reacted exothermically with I to yield the monomeric and dimeric addition products, EtC(OEt)2CN (II) and EtC(OEt)2CHMeC(OEt)2CN (III). I (16.0 g. ) in 300 cc. Et2O at 25 ° treated with stirring with 14.4 g. iodine during 1.75 h., the solvent and EtI distilled off at 9 mm., and the residue distilled gave 3.5 g. MeCHICO2Et (IV); 2.4 g. EtC(OEt)2CMe:C(OEt)2 (V), b0.25 47°, nD25 1.4305 (V first added and then substituted Br and slowly gave a green color with FeCl3); and 14.5 g. MeCHIC(OEt)2CHMeCO2Et (VI), b0.25 92°, nD25 1.4782 (VI when treated with Br or on standing liberated iodine). VI ( 13.2 g.) heated 15 min. at 210° gave 6.86 g. EtI-EtOH azeotrope; the dark brown residue yielded 0.95 g. Et α,γ-dimethyltetronate, b. 153-68°, nD25 1.4731, which hydrolyzed gave the free acid, m. 121.5-2.5°. V (6.85 g.) and 1.52 g. H2O heated 0.5 h. with stirring at 85-95°, and the solution dried and distilled gave 2.65 g. EtCOCHMeCO2Et, which yielded a pyrazolone, m. 108-10°. I (16.5 g.) added dropwise during 1 h. to 25.2 g. iodine in 500 cc. Et2O at 25° and the solution distilled gave 18.5 g. IV and 5.3 g. VI. Iodine (2.17 g.) in 28 cc. Et2O added during 1 h. to 11.1 g. I in 117 cc. Et2O at 0° and the mixture distilled gave 8.0 g. unchanged I, 1.75 g. V, and 1.05 g. VI. Iodine (61.0 g.) in 450 cc. Et2O treated with stirring at 0-5° with 31.2 g. I during 40 min., the light yellow, supernatant liquid forced through a filter stick, the remaining solid treated with 200 cc. cold Et2O and 25 cc. cold H2O, the mixture titrated with aqueous Na2S2O3 until colorless (0.118 mol iodine was present), the aqueous layer titrated with base (0.058 mol acid present), and the Et2O layer distilled gave 11.8 g. IV; these titrations showed the salt to be [MeCHIC(OEt)2]I5. Iodine (119.8 g.) in 800 cc. Et2O treated at about -3° with 20.4 g. I during 15 min., and the heavy brown precipitate worked up and titrated in the usual manner, and finally treated with H2O gave 22.5 g. IV. Iodine (49.6 g.) and 25.4 g. mixed with 100 cc. cold Et2O, the Et2O suspension treated with 27.7 g. I, and the mixture worked up gave 6.6 g. IV, 7.0 g. V, 20.4 g. VI, and 3.5 g. unchanged I. I (10.2 g.) in 100 cc. Et2O treated with 21.3 g. iodine in 200 cc. Et2O at 0° during 3 h., and the orange solution distilled gave 18.1 g. Me2CHICO2Et, b12 64°, nD25 1.5010. I (21.0 g.) in 100 cc. CCl4 added during 35 min. with stirring at -5° to 98.5 g. Br in 200 cc. CCl4, the solvent removed through a filter stick, the residual heavy, granular, red solid shaken with 20 cc. cold H2O, the mixture treated with 100 g. KI in H2O and titrated with Na2S2O3 (0.303 mol Br present), and the organic layer extracted and distilled gave 12.2 g. MeCHBrCO2Et (VII); the CCl4 filtrate (from the red solid) shaken with 76 g. KI in H2O, decolorized with 0.345 equivalent Na2S2O3, and distilled gave 8.8 g. VII. I (10.6 g.) in 40 cc. CCl4 added during 1 h. at 0° to 12.5 g. Br in 60 cc. CCl4 gave 2.1 g. orange solid which contained 58.3% Br (dried at 0.1 mm. and 0°). I (2.6 g.) added to 6.4 g. Br in 8 cc. CCl4 at -25 to -30° gave 4.1 g. red solid containing 69.5% Br. I (30.1 g.) added at 0° during 40 min. to 20.2 g. ICl in 100 cc. CCl4 and the mixture distilled twice gave 5.4 g. MeCHClCO2Et, 9.1 g. IV, 7.9 g. V, and 5.7 g. VI. (CN)2 bubbled through 18.3 g. I at 100° with stirring during 3 h. and distilled gave only 16.0 g. unchanged I. I (51.1 g.) added slowly with stirring during 25 min. to 47.1 g. BrCN in 70 cc. Et2O and distilled gave 90.4 g. MeCHBrC(OEt)2CN (VIII), b16 108°, nD25 1.4463, d25 1.2611. I (19.6 g.) in 150 cc. Et2O treated with stirring with 18.0 g. BrCN in 50 cc. Et2O an distilled gave 28.9 g. VIII. VIII (6.00 g.) shaken 8 h. with 4.32 g. AgNO3 in 150 cc. Et2O, and the precipitate filtered, washed with Et2O, and dried gave 3.5 g. AgCN; the aqueous layer contained 0.181 mol acid; the Et2O washings distilled gave 3.5 g. VII, b14 54°, nD25 1.4427. VIII (10 g.) refluxed (210°) 5.5 h., and the HCN evolved passed into aqueous AgNO3 gave 1.2 g. AgCN; the residue distilled gave 23% impure VII, nD25 1.4414-1.4433. I (9.7 g.) added dropwise to 11.4 g. ICN in 50 cc. Et2O and distilled gave 18.5 g. MeCHIC(OEt)2CN, b0.15 84-9°, nD25 1.4798. I (11.8 g.) added with stirring to 2.45 g. HCN at -10° and distilled gave 12.2 g. II, b10 62-3°, nD25 1.4040, d25 0.9113, MRD 42.19; and 0.5 g. III, b0.25 70°, nD25 1.4330, 0.9641, MRD 77.53. I (17.1 g.) treated with cooling with 3.9 g. liquid HCN during 20 min. and the mixture kept 1.5 days at 25° and distilled gave 14.6 g. II and 4.7 g. XIII.
Compound(3400-55-3)Synthetic Route of C7H15BrO2 received a lot of attention, and I have introduced some compounds in other articles, similar to this compound(2-Bromopriopionaldehydediethylacetal), if you are interested, you can check out my other related articles.
Reference:
Piperazine – Wikipedia,
Piperazines – an overview | ScienceDirect Topics