53811-50-0Relevant academic research and scientific papers
Palladium-catalyzed ortho-C(sp2)[sbnd]H bromination of benzaldehydes via a monodentate transient directing group strategy
Yong, Qiyun,Sun, Bing,Zhang, Fang-Lin
supporting information, (2019/11/03)
A facile and efficient monodentate transient directing group strategy was developed to enable the palladium-catalyzed ortho-C(sp2)[sbnd]H bromination of benzaldehydes. A broad scope of benzaldehydes were transformed into the desired products by employing 2-amino-5-chlorobenzotrifluoride as a monodentate transient directing group, demonstrating good functional group tolerance. Mild reaction conditions and no requirement for a silver salt are also features of this strategy.
Fibrauretine synthetic method (by machine translation)
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Paragraph 0046; 0047; 0063, (2018/09/21)
The invention relates to O-vanillin (11) as the starting material, by the acylation reaction generating 2 - acetoxy - 3 - methoxybenzaldehyde (12), by the bromo, hydrolysis reaction to produce the 2 - hydroxy - 6 - bromo - 3 - methoxybenzaldehyde (13), produced by the methylation reaction 6 - bromo - 2, 3 - dimethoxy benzaldehyde (14), produced by the condensation reaction of 2 - (6 - bromo - 2, 3 - dimethoxyphenyl) - 1, 3 - dioxolane (15); and then to 3, 4 - dimethoxy acetic acid (21) as raw materials, generated by the reduction reaction of the 3, 4 - dimethoxy ethanol (22), the acylation reaction generated by 3, 4 - dimethoxy new valeric acid environmentally (23), the acylation reaction is generated by the 2 - ethoxy - 3, 4 - dimethoxy new valeric acid environmentally (24), intermediate (15) and (24) after coupling, cyclized two-step reaction process for preparing the target product fibrauretin. (by machine translation)
Modular, Metal-Catalyzed Cycloisomerization Approach to Angularly Fused Polycyclic Aromatic Hydrocarbons and Their Oxidized Derivatives
Thomson, Paul F.,Parrish, Damon,Pradhan, Padmanava,Lakshman, Mahesh K.
, p. 7435 - 7446 (2015/08/18)
Palladium-catalyzed cross-coupling reactions of 2-bromobenzaldehyde and 6-bromo-2,3-dimethoxybenzaldehyde with 4-methyl-1-naphthaleneboronic acid and acenaphthene-5-boronic acid gave corresponding o-naphthyl benzaldehydes. Corey-Fuchs olefination followed by reaction with n-BuLi led to various 1-(2-ethynylphenyl)naphthalenes. Cycloisomerization of individual 1-(2-ethynylphenyl)naphthalenes to various benzo[c]phenanthrene (BcPh) analogues was accomplished smoothly with catalytic PtCl2 in PhMe. In the case of 4,5-dihydrobenzo[l]acephenanthrylene, oxidation with DDQ gave benzo[l]acephenanthrylene. The dimethoxy-substituted benzo[c]phenanthrenes were demethylated with BBr3 and oxidized to the o-quinones with PDC. Reduction of these quinones with NaBH4 in THF/EtOH in an oxygen atmosphere gave the respective dihydrodiols. Exposure of the dihydrodiols to N-bromoacetamide in THF-H2O led to bromohydrins that were cyclized with Amberlite IRA 400 HO- to yield the series 1 diol epoxides. Epoxidation of the dihydrodiols with mCPBA gave the isomeric series 2 diol epoxides. All of the hydrocarbons as well as the methoxy-substituted ones were crystallized and analyzed by X-ray crystallography, and these data are compared to other previously studied BcPh derivatives. The methodology described is highly modular and can be utilized for the synthesis of a wide variety of angularly fused polycyclic aromatic hydrocarbons and their putative metabolites and/or other derivatives.
Short and efficient syntheses of protoberberine alkaloids using palladium-catalyzed enolate arylation
Gatland, Alice E.,Pilgrim, Ben S.,Procopiou, Panayiotis A.,Donohoe, Timothy J.
supporting information, p. 14555 - 14558 (2015/02/19)
A concise synthesis of the biologically active alkaloid berberine is reported, and a versatile palladiumcatalyzed enolate arylation is used to form the isoquinoline core. The overall yield of 50%is a large improvement over the single, previous synthesis. By design, this modular route allows the rapid synthesis of other members of the protoberberine family (e.g., pseudocoptisine and palmatine) by substitution of the readily available aryl bromide and ketone coupling partners. Moreover, by combining enolate arylation with in situ functionalization, substituents can be rapidly and regioselectively introduced at the alkaloid C13 position, as demonstrated by the total synthesis of dehydrocorydaline. The avoidance of electrophilic aromatic substitution reactions to make the isoquinoline allows direct access to analogues possessing more varied electronic properties, such as the fluorine-containing derivative synthesized here.
Modular isoquinoline synthesis using catalytic enolate arylation and in situ functionalization
Pilgrim, Ben S.,Gatland, Alice E.,McTernan, Charlie T.,Procopiou, Panayiotis A.,Donohoe, Timothy J.
supporting information, p. 6190 - 6193 (2014/01/17)
A methyl ketone, an aryl bromide, an electrophile, and ammonium chloride were combined in a four-component, three-step, and one-pot coupling procedure to furnish substituted isoquinolines in overall yields of up to 80%. This protocol utilizes the palladiu
Selective ortho -bromination of substituted benzaldoximes using Pd-catalyzed C-H activation: Application to the synthesis of substituted 2-bromobenzaldehydes
Dubost, Emmanuelle,Fossey, Christine,Cailly, Thomas,Rault, Sylvain,Fabis, Frederic
experimental part, p. 6414 - 6420 (2011/09/16)
Substituted 2-bromobenzaldehydes were synthesized from benzaldehydes using a three-step sequence involving a selective palladium-catalyzed ortho-bromination as the key step. O-Methyloxime serves as a directing group in this reaction. A rapid deprotection of substituted 2-bromobenzaldoximes afforded substituted 2-bromobenzaldehydes with good overall yields.
Structure-activity relationship studies of phenanthridine-based Bcl-X L inhibitors
Bernardo, Paul H.,Wan, Kah-Fei,Sivaraman, Thirunavukkarasu,Xu, Jin,Moore, Felicity K.,Hung, Alvin W.,Mok, Henry Y. K.,Yu, Victor C.,Chai, Christina L. L.
experimental part, p. 6699 - 6710 (2009/10/23)
Despite their structural similarities, the natural products chelerythrine (5) and sanguinarine (6) target different binding sites on the pro-survival Bcl-XL protein. This paper details the synthesis of phenanthridine-based analogues of the natu
Synthesis of (+/-)-8-Oxotetrahydropalmatine and (+/-)-Gusanlung B
Nimgirawath, Surachai,Ponghusabun, Ong-ard
, p. 951 - 956 (2007/10/02)
The 8-oxotetrahydroprotoberberine alkaloids (+/-)-8-oxotetrahydropalmatine and (+/-)-gusanlung B have been synthesized by radical-initiated 1,6-cyclization of the corresponding 2-arylcarbonyl-1-methylenetetrahydroisoquinolines.
TETRAHYDRO-6,7-DIMETHOXY-1H-BENZ[E]ISOINODOLINES USEFUL IN THE TREATMENT OF HYPERTENSION AND AS SEDATIVES
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, (2008/06/13)
Disclosed herein are tetrahydro-benzo e!isoindolines represented by the formula STR1 wherein R, R 1 and R 2 are independently selected from hydrogen, loweralkyl of 1 to 4 carbon atoms, hydroxy, loweralkoxy of 1 to 3 carbon atoms, allyloxy, benzyloxy, benzoyloxy, thiomethyl, halo, STR2 wherein t is 0 or 1, n is 0 to 5 and R 11 and R 14 are independently selected from hydrogen, halo, hydroxy, loweralkyl of 1 to 4 carbon atoms, loweralkoxy of 1 to 3 carbon atoms or amino; orR and R. sub.1, or R 1 and R 2 can be taken together to form a methylenedioxy or ethylenedioxy bridge; with the proviso that at least one of R, R 1 or R 2 must be other than hydrogen and the proviso that two of R, R 1, or R 2 must be other than methoxy in the 7 and 8 positions when the remaining one of R, R 1 or R 2 is hydrogen; andR 3 is hydrogen, loweralkyl of 1 to 4 carbon atoms, halo-substituted loweralkyl of 1 to 4 carbon atoms, amino-substituted loweralkyl of 1 to 4 carbon atoms, amino-substituted arylalkyl, allyl, thioloweralkyl, loweralkanol, or STR3 wherein R 12 and R 13 are independently selected from hydrogen, hydroxy, amino, loweralkoxy of 1 to 3 carbon atoms and s is 1 to 3; or STR4 wherein m is 0, 1 or 2, p is 0 or 1, R 7 is hydrogen or loweralkyl of 1 to 4 carbon atoms and R 8 and R 9 are independently selected from hydrogen, hydroxy, methoxy, loweralkyl of 1 to 4 carbon atoms, or halo, or R 8 and R 9 can be taken together to form a methylenedioxy or ethylenedioxy bridge; or 1,4-benzodioxan of the formula STR5 wherein q is 1, 2 or 3, and R 10 is hydrogen, methoxy, amino, or halo; and the pharmaceutically acceptable salts thereof.
3-ETHOXY-2-HYDROXYBENZALDEHYDE AS A STARTING COMPOUND FOR SYNTHESIS OF ISOQUINOLINE ALKALOIDS
Smidrkal, Jan
, p. 2140 - 2144 (2007/10/02)
3-Ethoxy-2-hydroxybenzaldehyde (I) was used to prepare 6-bromo-2,3-dihydroxybenzaldehyde (V), 6-bromo-2,3-methylenedioxybenzaldehyde (VIa), 6-bromo-2,3-methylenedioxybenzoic acid (VIIa), and for new synthesis of compounds II, IIIa, IIIb, IV, VIb, VIIb, VIIIa, VIIIb, IXa and IXb.
