Showing papers on "Grignard reaction published in 1985"
69 citations
TL;DR: Bis(allylic) palladium complexes can be induced to undergo reductive elimination by replacement of phosphine ligands in the system with π-acidic ligands as discussed by the authors.
59 citations
TL;DR: Synthese en particulier de tricosene-9, heneicosenesene-6one-11, undecene-4al, nonadecene-7one11, tridecene -4ol-1, isovalerate de decene-5ol 1 a partir de reaction de Grignard appliquee au dihydro-3,4 pyranne.
Abstract: Synthese en particulier de tricosene-9, heneicosene-6one-11, undecene-4al, nonadecene-7one-11, tridecene-4ol-1, isovalerate de decene-5ol-1 a partir de reaction de Grignard appliquee au dihydro-3,4 pyranne
47 citations
26 citations
TL;DR: In this paper, the reactions of Grignard reagents with methyl 2-acetamidoacrylate in the presence of CuI give fair yields of α-amino esters; the corresponding α-deutero- or α-methyl-derivatives are obtained upon quenching with D + or CH 3 I, respectively.
23 citations
TL;DR: In this paper, an ionophorous polyether antibiotic, salinomycin, corresponding to the C-21∼C-30 fragment (the right fragment) of 1 was synthesized from D-mannitol and ethyl L-lactate as chiral starting materials.
20 citations
TL;DR: In this article, arylaminyl radicals derived from the reagents were detected by ESR in low concentrations and identified by computer simulation, from comparison of all the itemized facts characteristic of the reaction with those of Grignard reaction of the same substrates, the mechanisms of initial coordination and electron transfer of the two reactions were distinguished.
Abstract: In the reaction of aryliminodimagnesium reagents(ArN(MgBr)2, Ar=C6H5, p-MeC6H4, and p-MeOC6H4) with some p-substituted benzophenones, the arylaminyl radicals(ArNMgBr) derived from the reagents were detected by ESR in low concentrations and identified by computer simulation. From comparison of all the itemized facts characteristic of the reaction with those of Grignard reaction of the same substrates, the mechanisms of initial coordination and electron transfer of the two reactions were distinguished.
20 citations
TL;DR: In this paper, 6-(Methylthio)purine reacted with RMgX (R=C6H5, CH3(CH2)nCH2 (n=2 to 6), C6H 5CH2CH2, (CH3)2 C=CHCH2Ch2) in the presence of 5 mol% [NiCl2(Ph2PCH2 CH2CH 2CH2PPh2] in refluxing THF for 8 h to afford 6-aryl or 6-alkylpurines in 62-74
Abstract: 6-(Methylthio)purine reacted with RMgX (R=C6H5, CH3(CH2)nCH2 (n=2 to 6), C6H5CH2CH2, (CH3)2 C=CHCH2CH2) in the presence of 5 mol% [NiCl2(Ph2PCH2CH2CH2PPh2)] in refluxing THF for 8 h to afford 6-aryl or 6-alkylpurines in 62–74% yields. By applying this reaction to 6-(methylthio)purine nucleoside, 6-(4-methyl-3-pentenyl)-9-β-D-ribofuranosylpurine was synthesized.
19 citations
19 citations
TL;DR: Chiral N-methyl-4-phenyl-1, 3-oxazolidines (2a-e) having a methyl, ethyl, benzyl, isopropyl, and cyclohexyl group at the 2-position of the 1, 3, oxazolidine ring were synthesized as mentioned in this paper.
Abstract: Chiral N-methyl-4-phenyl-1, 3-oxazolidines (2a-e) having a methyl, ethyl, benzyl, isopropyl, and cyclohexyl group at the 2-position of the 1, 3-oxazolidine ring were synthesized. Reactions of 2a-e with Grignard reagents gave (1R, 1'R)- and (1S, 1'R)-1-alkyl-and 1-cycloalkyl-N-2'-hydroxy-1'-phenylethyl-2-phenylethylamines (3a, 3b, 3d, 3e). The absolute configurations of (1R, 1'R)-3a and-3e were determined. (R)-1-Methyl-and (R)-1-cyclohexyl-2-phenylethylamines (4a, 4e) were obtained in high yield by hydrogenolysis of (1R, 1'R)-3a and -3e.
17 citations
Patent•
03 Apr 1985
TL;DR: In this paper, a novel polymer of triphenylamine, which may be a homopolymer of 4,4',4"-triphenylamines units, a copolymer of 1,4-benzene units and 4, 4-, 4-, 1, 4"-triphenamine units, was presented.
Abstract: A novel polymer of triphenylamine, which may be a homopolymer of 4,4',4"-triphenylamine units, a copolymer of 4,4',4"-triphenylamine units and 1,4-benzene units or a homopolymer of 4,4'-(4"-unsubstituted or 4"-alkyl or alkoxyl) triphenylamine. This polymer is prepared by first carrying out Grignard reaction between a halogenotriphenylamine and metallic magnesium and then polymerizing the obtained Grignard reagent in a nonreactive organic solvent by using a nickel compound catalyst. This polymer acquires high conductivity by doping with an electron accepting dopant, and the conductivity is stable in the atmosphere. This polymer is useful as an electrode material in a device using a liquid electrolyte and is advantageous in being stable to repetition of electrochemical oxidation and reduction.
TL;DR: In this paper, it was shown that 1,2,3-triazines reacted with Grignard reagents to form adducts due to N-2 and C-5 attack together with β-substituted acrylaldehydes and N--substitized pyrazoles.
Abstract: Monocyclic 1,2,3-triazines reacted with Grignard reagents to form adducts due to N-2 and C-5 attack together with β-substituted acrylaldehydes and N--substituted pyrazoles; the results show that the N-2,C-4 and C-5 positions are reactive towards Grignard reagents.
TL;DR: In this article, the Grignard products generated during the preparation of phenylmagnesium bromide in peroxide-free ether, the prepared compound was quenched with H2O or D2O, and the products quantitatively determined by gas chromatography and GC coupled with mass spectrometry.
TL;DR: In this paper, the ecdysone side chain starting from pregnenolone was achieved via a furan derivative, whose reduction over rhodium-alumina, followed by ruthenium tetroxide oxidation, gave the lactones in a ratio of ca. 1:1.
Abstract: Construction of the ecdysone side chain starting from pregnenolone was achieved via a furan derivative. Reduction of the olefinic-furan over palladium–carbon afforded the hydrogenated furan derivative with the desired stereochemistry at C-20, exclusively, whose subsequent reduction over rhodium–alumina, followed by ruthenium tetroxide oxidation, gave the lactones in a ratio of ca. 1:1. Grignard reaction of both lactones with methylmagnesium bromide led to the synthesis of the triols having ecdysone-type side chains, respectively.
TL;DR: In this paper, 6-Phenoxy-2-pyridine carbaldehyde was prepared in good yields through a few reaction steps utilizing Grignard reaction which has been regarded disadvantageous for preparation of pyridinecarbaldehydes.
Abstract: 6-Phenoxy-2-pyridinecarbaldehyde was prepared in good yields through a few reaction steps utilizing Grignard reaction which has been regarded disadvantageous for preparation of pyridinecarbaldehydes.
Patent•
14 Feb 1985TL;DR: In this article, a process for the preparation of intermediates in the synthesis of biotin and biotin itself is described, where the side chain is attached by means of a Grignard reaction to the ring system, the compound obtained is dehydrated and then reduced.
Abstract: There is described a process for the preparation of intermediates in the synthesis of biotin and biotin itself. Here, the side chain is attached by means of a Grignard reaction to the ring system, the compound obtained is dehydrated and then reduced.
TL;DR: In this paper, 4-Bromobenzophenone was converted to (4-bromophenyl)-phenyldichloromethane using phosphorus pentachloride and was subsequently converted to its Grignard reagent, carboxylated with 14CO2, and acid hydrolyzed to the final product.
Abstract: [1-14C-Carboxy]-4-benzoylbenzoic acid has been prepared via a Grignard reaction with 14CO2. 4-Bromobenzophenone was converted to (4-bromophenyl)-phenyldichloromethane using phosphorus pentachloride. The dichloro compound was reacted with methoxide ion to form 4-bromobenzophenone dimethylketal which was subsequently converted to its Grignard reagent, carboxylated with 14CO2, and acid hydrolyzed to the final product. Using excess Grignard reagent, virtually quantitative conversion of 14CO2 to product was obtained.
TL;DR: A range of 1-(2-propenyl) alcohols was transformed in good yields into vinyl-oxiranes via the allylic bromide as mentioned in this paper, which was then used to convert the alcohols to vinyl.
TL;DR: The coupling reaction of isoprene bromohydrin with aryl and alkyl Grignard reagents catalyzed by tetrakis(triphenylphosphine)palladium(0) selectively gave the vinyl-group-migrated products.
Abstract: The coupling reaction of isoprene bromohydrin with aryl and alkyl Grignard reagents catalyzed by tetrakis(triphenylphosphine)palladium(0) selectively gave the vinyl-group-migrated products.
TL;DR: Synthese a partir de la methyl-1 piperidone-4, de lamethyl 1 piperazine and de la tropanone-3.
Abstract: Synthese a partir de la methyl-1 piperidone-4, de la methyl-1 piperazine et de la tropanone-3
TL;DR: In this paper, a synthesis of 4-(1,5,9-trimethyl-1,vinyl-4,8-decadienyl)catechol dimethyl ether was described utilizing Wittig reaction for the introduction of vinylic substituent at the quaternary carbon.
Abstract: Synthesis of 4-(1,5,9-trimethyl-1-vinyl-4,8-decadienyl)catechol dimethyl ether has been described utilizing Wittig reaction for the introduction of vinylic substituent at the quaternary carbon.
TL;DR: In this paper, the Grignard reaction of 2-morpholino and 2-methylthio-3-cyanoquinoline with alkyl or aryl magnesium halides has been studied.
Abstract: Abstract Grignard reactions of 2-morpholino and 2-methylthio-3-cyanoquinoline, 2-chloro-3-cyanoquinoline, 2-chloro-3-cyano-6-methoxyquinoline and 2-chloro-3-cyano-7-methylquinoline with alkyl or aryl magnesium halides have been studied. It was found that 2-morpholino and 2-methylthio- 3-cyanoquinolines gave 1,4-addition products followed by rapid aromatisation. 2-Chloro-3- cyanoquinoline with alkyl magnesium halides furnished 1,4-addition products but with aryl magnesium halides 1,4- and 1,2-addition products were obtained. The cyano group of 4-aryl-2-chloro- 3-cyano-1,4-dihydroquinolines was found to participate in the Grignard reaction to yield 1,2- addition products. 2-Chloro-3-cyano-6-m ethoxyquinoline with alkyl and phenyl magnesium halides yielded exclusively 1,4-addition products. Similarly with p-m ethoxyphenyl magnesium bromide, 1,4-addition products were isolated which participated in the Grignard reaction to yield the expected adducts. Unlike the other chloroquinoline derivatives, 2-chloro-3-cyano-7-methylquinoline with alkyl magnesium halide formed 1 ,2-addition products but with aryl magnesium halides, 1,4-addition products were isolated. The 4-alkyl-2-chloro-3-cyano-l,4-dihydroquinolines were unstable as compared to their 4-aryl analogs. A couple of the Grignard reaction products were found to be unstable on activated surface.
Patent•
30 Dec 1985
TL;DR: In this paper, a disubstituted bicyclo[2.2.1] heptane was obtained by subjecting cyclopentadiene to a Diels-Alder reaction with an unsaturated ketone, this reaction being catalyzed by a Lewis acid.
Abstract: Novel disubstituted bicyclo[2.2.1]heptanes of the general formula I ##STR1## where R 1 is C 1 -C 3 -alkyl, R 2 is C 1 -C 8 -alkyl or-alkenyl, R 3 and R 4 together are ═O, ═CH--CN, ═CH--CO--OCH 3 or ═CH--CO--OC 2 H 5 , or R 3 is hydrogen, --CH 3 , --CH═CH 2 or --C.tbd.CH when R 4 is --OH or --O--CO--CH 3 , or R 3 is H when R 4 is --CH 2 --CO--OCH 3 , --CH 2 --CO--OC 2 H 5 or --CH 2 --C.tbd.N and one or both of the dashed lines may be a further bond, are obtained by subjecting cyclopentadiene to a Diels-Alder reaction with an unsaturated ketone, this reaction being catalyzed by a Lewis acid, and then subjecting the compound of the formula Ia ##STR2## initially formed to a reduction, a Grignard reaction or a reaction with diethylphosphonoacetonitrile or ethyl phosphonoacetate and NaH. They can be used as scents and/or aromas or as intermediates for scents.
TL;DR: In this paper, the reaction of 4-Aroylquinazolines (3) with sodium hydroxide in dimethyl sulfoxide (DMSO) was found to proceed in two ways.
Abstract: 4-Aroylquinazolines (3) were prepared in good yields by alkaline hydrolysis of α-aryl-4-quinazolinylmethyl benzoates (15), followed by oxidation. The reaction of 3 with sodium hydroxide in dimethyl sulfoxide (DMSO) was found to proceed in two ways. One path is the aryl migration to lead to 4-aryl-3, 4-dihydro-4-quinazolinecarboxylic acids (4), and the other is the fission of the C4-CO bond to yield quinazoline (5) and aroic acids (6). Potassium ferricyanide oxidized the carboxylic acids 4 to the corresponding 4-arylquinazolines (14) with elimination of carbon dioxide. Reaction of 4-benzoylquinazoline (3a) with methylmagnesium iodide did not result in the migration, but instead yielded of α-methyl-α-phenyl-4-quinazolinemethanol (18) and 3, 4-dihydro-α, 4-dimethyl-α-phenyl-4-quinazolinemethanol (19).
TL;DR: In this article, the Grignard reaction of substituted 3-oxa-7-azabicyclo with propargylmagnesium bromide has been used to prepare tertiary alcohols.
Abstract: Von substituierten 3-Oxa-7-azabicyclo[331]nonan-9-onen abgeleitete tertiare Alkohole werden durch Grignard-Reaktion der Ketone mit Propargylmagnesiumbromid erhalten Die Stereoselektivitat dieser Reaktionen ist sehr hoch 1H-NMR- und IR-Spektren werden diskutiert
Tertiary 3-Oxa-7-azabicyclo[331]nonan-9-oles
Tertiary alcohols are prepared by Grignard reaction of substituted 3-oxa-7-azabicyclo[331]nonan-9-ones with propargylmagnesium bromide A very high stereoselectivity of these reactions is observed The 1H-NMR and IR spectra of the alcohols are discussed
TL;DR: The carboxylic acid ester (3) as discussed by the authors is an analogue of prostaglandin J2 and contains an allene moiety at C12, and is available from 7-chloronorbornadiene (5) in a route which has two key steps.
Abstract: A new class of prostanoid has been synthesized. The carboxylic acid ester (3) is an analogue of prostaglandin J2 and contains an allene moiety at C12. The novel compound (3) is available from 7-chloronorbornadiene (5) in a route which has two key steps. The first is the reaction of (5) with an alkynyl Grignard reagent to give the dienyne (7). The second is the regioselective epoxidation of the dienyne (7), rearrangement of the epoxide (8) to give the aldehyde (9), followed by an oxa-Cope rearrangement; the derived enol (10) was hydrolysed to give the useful prostaglandin synthon (14) directly.
Patent•
26 Feb 1985TL;DR: In this article, a process for the manufacture of intermediates in the synthesis of biotin as well as of the biotin itself is described, in which the side chain is attached to the ring system by means of a Grignard reaction, the resulting compound is then dehydrated and subsequently reduced.
Abstract: A process for the manufacture of intermediates in the synthesis of biotin as well as of biotin itself is described. In this process the side chain is attached to the ring system by means of a Grignard reaction, the resulting compound is then dehydrated and subsequently reduced.
Patent•
05 Mar 1985
TL;DR: In this article, a benzoic acid derivative shown by the formula I (X is group shown by formula II, formula III, or formula IV) and its salt is used to remedy various kinds of disease such as thrombosis, myocardial infarction, diabetic vascular complication, asthma etc.
Abstract: NEW MATERIAL:A benzoic acid derivative shown by the formula I (X is group shown by the formula II, formula III, or formula IV) and its salt. EXAMPLE:p-(3-Pyridylmethoxymethyl)benzoate hydrochloride. USE:An inhibitor against an enzyme synthesizing thromboxane A2. Useful for remedying various kinds of disease such as thrombosis, myocardial infarction, diabetic vascular complication, asthma, etc. resulting from thromboxane A2. PREPARATION:Nicotinic aldehyde is condensed with malonic acid to give a reaction product, which is converted in HCl-containing methanol by heating to give a compound shown by the formula V. This compound is hydrogenated in a solvent in the presence of Pd/C catalyst at normal pressure, which is subjected to Grignard reaction with p-diethoxymethylphenylmagnesium bromide, and treated with a mineral acid to give a compound(novel compound) shown by the formula VI, which is oxidized with an oxidizing agent in a mixed solvent to give a compound shown by the formula I where X is a group shown by the formula II.