Synthesis of 3,4,5-trimethoxybenzaldehyde , Hive …
3,4,5-Trimethoxybenzaldehyde is used as an intermediate for the synthesis of ..
Preparation of 3,4,5-trimethoxybenzaldehyde: Chemistry Discourse :
2, 3-Dimethoxy-5-methyl-p-benzoquinone (3), an important intermediate in the synthesis of ubiquinones (1), was synthesized from 3, 4, 5-trimethoxysalicylic acid (6) or 2, 3, 4-trimethoxybenzaldehyde (9). 6 was reduced via the ethoxycarbonyl derivative (7) to 6-methyl-2, 3, 4-trimethoxyphenol (8) with sodium borohydride, and then 8 was oxidized to 3 in high yield with ferric chloride. On the other hand, 2, 3, 4-trimethoxyphenol (10) was obtained from 9 by the Baeyer-Villiger reaction or treatment with hydrogen peroxide under acidic or basic conditions, and then converted into 8 by reductive methylation. Sodium borohydride reduction of the Mannich base (11) of 10 also gave 8.
Please feel free to for:3,4,5-Trimethoxybenzaldehyde
Quotation (3,4,5-Trimethoxybenzaldehyde price),COA (Certificate of Analysis),
New Sales Promotion,New Products,And any other assistance.
Asymmetric Total Syntheses of Colchicine, β …
1. sister’s noise
2. infinite synthesis
4. lost dimension
5. I’m believing you
6. Secret of my heart
7. eternal reality
8. black bullet
9. rain of tears
10. scorching heart
11. waiting for the moment
12. always be with you
13. true resonance
Subsequently, the proposed transition-metal-catalyzed decarbonylation/electrocyclic ring-opening cascade reaction of 3 was attempted using several different catalysts (Rh, Ni, and Pd) in a variety of different solvents, as reported previously. However, these conditions failed to afford any of the desired product of 2. To our delight, the irradiation of a solution of β-lumicolchicine (3) in 10:1 (v/v) CH3CN/acetone (0.0024 mol/L) with a 125 W high-pressure mercury arc lamp surrounded by a Pyrex water jacket for 20 min gave 2 in 54% yield instead of α-lumicolchicine (4) and colchicine. The outcome of this transformation suggested that under the irradiation compound 3 had probably undergone a decarbonylation process to generate the intermediate B, followed by the anticipated retro-4π-electrocyclization reaction to give 2, which has been reported to exhibit greater inhibitory activity toward tubulin than colchicine. The 1H and 13C NMR spectra of synthetic 2 and 3, as well as their optical rotation, were identical to those of the natural products. We also have tried to extend the time of irradiation for one-pot synthesis of compound 2 from 1, but a trace of 2 was detected. Probably, other unidentified compounds made the reaction more complex, with the time extended and the temperature of the solution increased. So, after many attempts, we found that 25 min is the best time length for the first irradiation and the two-step sequence is more efficient than the one-pot procedure for the preparation of 2 from 1.
SDS Search - EH&S - WKU - Western Kentucky University
Meyers’ 4-aryl-1-tetralone-lactone and -Zhang’s 2-diarylmethyl-4-oxobutanoate were synthesized in the formal synthesis of (−)-podophyllotoxin from (2,3)-3-arylaziridine-2-carboxylate, via 3,3-diarylpropanoate as a common intermediate, in an overall 42% yield through 10 steps and 31% yield through 6 steps, respectively. The key steps in the synthesis were regio- and diastereoselective ring opening with an aromatic nucleophile, samarium iodide promoted reductive C–N bond cleavage, and Stille coupling for introducing the vinyl functionality. The starting aziridine was enantioselectively prepared from 3,4,5-trimethoxybenzaldehyde by guanidinium ylide mediated asymmetric aziridination. All nitrogen components used in the reaction sequence are reusable as the starting guanidinium source.
Structurally, colchicine (1) possesses an unusual 6–7–7 tricyclic ring system, and NCME (2) possesses a 6–7–6 carbocyclic skeleton. The stereocenter at C-7 and the a-configured chiral axis defined by the pivot bond joining the A and C rings, and the regioselective construction of the highly oxidized tropolone C-ring, represent formidable synthetic challenges. It is noteworthy that another colchicinoid β-lumicolchicine (3) has a novel tetracyclic 6–7–4–5 membered ring system with three stereocenters, and α-lumicolchicine (4) has a unique nonacyclic 6–7–4–5–4–5–4–7–6 ring skeleton with ten stereocenters.
2, 4, 5-Trimethoxybenzaldehyde is found in carrot
Thieme E-Journals - Synthesis / Abstract
3,4,5-trimethoxybenzaldehyde - chemical structural formula, chemical names, chemical properties, synthesis references
3,4,5-Trimethoxybenzaldehyde from Gallic Acid (and …
Dehydrogenation of Chromanones and Flavanones by 2,3-Dichloro-5,6-dicyano-1,4 …
2,3,4-Trimethoxybenzaldehyde for synthesis | VWR
Get supplier listing of 3,4,5-Trimethoxybenzaldehyde and equal product
3,4,5-trimethoxybenzaldehyde | C10H12O4 - …
Retrosynthetically (), β-lumicolchicine (3) could be prepared from colchicine (1) through a 4π-electrocyclization reaction. We anticipate that NCME (2) would be synthesized from 3 through a Rh-catalyzed decarbonylation process via intermediate A to give the fused bicyclobutene B, followed by an electrocyclic ring-opening reaction. The formation of the more stable aromatic ring C is one of the driving forces for this process. It was envisioned that colchicine (1) could be generated from 6 through a Wacker oxidation, followed by the regioselective formation of the tropolone C-ring. Tricyclic 6 could itself be synthesized from 7 through the intramolecular oxidopyrylium-mediated [5 + 2] cycloaddition reaction. Compound 7 could be synthesized from 5 through several simple functional group transformations reported previously.
SDS Search - EH&S - Western Kentucky University
Owing to their unusual structural motifs and promising pharmacological properties, colchicine (1) and NCME (2) have attracted considerable attention from synthetic chemists, which has resulted in several elegant total syntheses of 1 and 2. Recently, we developed an enantioselective synthesis of colchicine (1) from commercially available and inexpensive 2,3,4-trimethoxybenzaldehyde (5). The challenging tricyclic 6–7–7 core of colchicinoids was efficiently introduced using an intramolecular oxidopyrylium-mediated [5 + 2] cycloaddition reaction. In our continuing efforts toward the synthesis of biologically active natural products, we herein describe a modified concise and highly enantioselective synthesis of colchicine using the Wacker oxidation for the regioselective construction of the highly oxidized tropolone C-ring. Moreover, asymmetric total syntheses of β-lumicolchicine and NCME were also achieved.
The total synthesis of (±)-allocolchicine has been completed by employing cobalt-catalyzed alkyne [2 + 2 + 2]-cyclotrimerization as the key reaction. The essential diyne has been synthesized from easily available 3,4,5-trimethoxybenzaldehyde following simple chemical transformations. In general, the cycloaddition gave a mixture of C(9) and C(10) isomers thus allowing the synthesis of both allocolchicine and its C(10)-carboxylate. Because this cycloaddition was employed at the penultimate stage, it allowed the synthesis of various analogues having the diverse functionality at C(9) and/or C(10) of ring C.
"I have always been impressed by the quick turnaround and your thoroughness. Easily the most professional essay writing service on the web."
"Your assistance and the first class service is much appreciated. My essay reads so well and without your help I'm sure I would have been marked down again on grammar and syntax."
"Thanks again for your excellent work with my assignments. No doubts you're true experts at what you do and very approachable."
"Very professional, cheap and friendly service. Thanks for writing two important essays for me, I wouldn't have written it myself because of the tight deadline."
"Thanks for your cautious eye, attention to detail and overall superb service. Thanks to you, now I am confident that I can submit my term paper on time."
"Thank you for the GREAT work you have done. Just wanted to tell that I'm very happy with my essay and will get back with more assignments soon."