99075-91-9Relevant academic research and scientific papers
Iodoarene-catalyzed oxidative transformations using molecular oxygen
Miyamoto,Yamashita,Narita,Sakai,Hirano,Saito,Wang,Ochiai,Uchiyama
supporting information, p. 9781 - 9784 (2017/09/07)
Molecular oxygen serves as a useful oxidant for the glycol scission of 1,2-diols and the Hofmann rearrangement of primary amides using pentamethyliodobenzene as a catalyst. The use of isobutyraldehyde and Lewis basic nitriles under O2 enabled the iodine(i)/(iii) catalytic cycle, where in situ-generated peracid acts as a terminal oxidant.
(Tosylimino)phenyl-λ3-iodane as a reagent for the synthesis of methyl carbamates via hofmann rearrangement of aromatic and aliphatic carboxamides
Yoshimura, Akira,Luedtke, Matthew W.,Zhdankin, Viktor V.
, p. 2087 - 2091 (2012/05/05)
A new, mild procedure for the Hofmann rearrangement of aromatic and aliphatic carboxamides using (tosylimino)phenyl-λ3-iodane, PhINTs, as a reagent is reported. Because of the mild reaction conditions, this method is particularly useful for the Hofmann rearrangement of substituted benzamides, which usually afford complex reaction mixtures with other hypervalent iodine oxidants. The mild reaction conditions and high selectivity in the reaction of carboxamides with PhINTs allow the isolation of the initially formed labile isocyanates or their subsequent conversion to stable carbamates by treatment with alcohols.
Kinetics and mechanism of the aminolysis of O-methyl S-aryl thiocarbonates in acetonitrile
Oh, Hyuck Keun
scheme or table, p. 1539 - 1542 (2011/12/04)
The aminolysis of O-methyl S-aryl thiocarbonates with benzylamines are studied in acetonitrile at -45.0°C. The βX (βnuc) values are in the range 0.62-0.80 with a negative cross-interaction constant, ρXZ = -0.42, which are interpreted to indicate a concerted mechanism. The kinetic isotope effects involving deuterated benzylamine nucleophiles (XC6H 4CH2ND2) are large, kH/kD = 1.29-1.75, suggesting that the N-H(D) bond is partially broken in the transition state by forming a hydrogen-bonded four-center cyclic structure. The concerted mechanism is enforced by the strong push provided by the MeO group which enhances the nucleofugalities of both benzylamine and arenethiolate from the putative zwitterionic tetrahedral intermediate.
Facile preparation of protected benzylic and heteroarylmethyl amines via room temperature Curtius rearrangement
Leathen, Matthew L.,Peterson, Emily A.
supporting information; experimental part, p. 2888 - 2891 (2010/06/14)
A step-wise, room temperature procedure for acyl azide formation and the subsequent Curtius rearrangement of phenyl and heteroaryl acetic acids is described. We have developed a protocol for room temperature Curtius rearrangement in MeOH or CHCl3 that provides an improvement over standard conditions, avoiding the use of additives or heat. This room temperature optimization of the Curtius rearrangement prevents the formation of side products often observed with benzylic acids, allowing access to a variety of benzylic and heteroarylmethyl amines.
Hofmann rearrangement of carboxamides mediated by hypervalent iodine species generated in situ from iodobenzene and oxone: Reaction scope and limitations
Zagulyaeva, Aleksandra A.,Banek, Christopher T.,Yusubov, Mekhman S.,Zhdankin, Viktor V.
supporting information; experimental part, p. 4644 - 4647 (2010/12/19)
Alkylcarboxamides can be converted to the respective amines by Hofmann rearrangement using hypervalent iodine species generated in situ from PhI and Oxone in aqueous acetonitrile. On the basis of this reaction, a convenient experimental procedure for the preparation of alkylcarbamates using Oxone as the oxidant in the presence of iodobenzene in methanol has been developed. An efficient method for direct conversion of substituted benzamides to the respective quinone derivatives by treatment with Oxone and iodobenzene in aqueous acetonitrile has also been found.
Rapid and convenient microwave-assisted synthesis of primary amines via reductive N-alkylation of methyl carbamate with aldehydes
Lehmann, Fredrik,Scobie, Martin
, p. 1679 - 1681 (2008/12/22)
Microwave-assisted reductive alkylation of methyl carbamate with a range of aldehydes provides, after basic work-up, an experimentally simple, one-pot method for rapid functional group interconversion of structurally diverse aldehydes into primary amines. The method has several advantages over more traditional methods of carrying out this transformation and is particularly amenable to high-throughput synthesis.
A new route to 7-substituted derivatives of N-{4-[2-(2-amino-3,4-dihydro-4-oxo-7H-pyrrolo[2,3-d]pyrimidin-5-yl) -ethyl]benzoyl}-L-glutamic acid [ALIMTA (LY231514, MTA)]
Taylor,Liu
, p. 3726 - 3738 (2007/10/03)
Alkylation of various primary amines with crotyl bromide, followed by DMAP-promoted acylation with methyl malonyl chloride to 4 and then manganic triacetate dihydrate/cupric acetate induced radical cyclization, gave 1-substituted-4-vinyl-3-carbomethoxy-2-pyrrolidinones (5). Thiation to the thiolactams 6 and guanidine cyclization then gave a series of 2-amino-3,4-dihydro-4-oxo-5-vinyl-7-substituted pyrrolo[2,3-d]pyrimidines (7). Palladium-catalyzed C-C coupling with diethyl 4-iodobenzoylglutamate led in one step via an unexpected redox reaction to the diethyl esters 9 of a series of 7-substituted derivatives of ALIMTA (LY231514, MTA), from which the target analogues 10 were readily prepared by saponification. Attempted deprotection at position 7 was successful in only one case (9d, R = CH2C6H3(OMe)2 (-3′,4′), which resulted in a known pentultimate precursor (9, R = H) of ALIMTA. The 7-substituted derivatives 10 proved to be inactive in vitro as inhibitors of cell division.
A novel synthetic route to 7-substituted derivatives of the antitumor agent LY231514 (MTA)
Taylor, Edward C.,Liu, Bin
, p. 5291 - 5294 (2007/10/03)
This paper describes a further synthesis of the pyrrolo[2,3- d]pyrimidine antitumor agent MTA (LY231514). Manganic triacetate dihydrate- induced radical cyclization of methyl N-crotyl-N-(3',4'- dimethoxybenzyl)malonamide (4d) yielded the 3-carbomethoxy-2-pyrrolidinone 5d that was then thiated with P2S5 to the corresponding thiolactam (6d). Cyclization with guanidine gave the 7-substituted 2-amino-4(3H)-oxo-5,6- dihydro-pyrrolo[2,3-d]pyrimidine (7d). Pd-catalyzed coupling with diethyl 4- iodobenzoylglutamate yielded (in a single step) the diethyl ester 9d. Deprotection with H2SO4/TFA followed by saponification then gave MTA. Several additional 7-substituted derivatives of MTA were prepared by use of this methodology. In contradiction to a published claim, these 7-substituted derivatives proved to be devoid of any significant cell growth inhibitory activity.
