24486-06-4Relevant articles and documents
Rhodium-catalyzed direct coupling of benzothioamides with alkenes and alkynes through directed C-H bond cleavage
Yokoyama, Yuki,Unoh, Yuto,Bohmann, Rebekka Anna,Satoh, Tetsuya,Hirano, Koji,Bolm, Carsten,Miura, Masahiro
supporting information, p. 1104 - 1106 (2015/09/02)
Rhodium-catalyzed direct coupling of benzothioamides with alkenes proceeds smoothly involving ortho-CH bond cleavage. The thioamides also couple with alkynes under similar conditions accompanied by desulfurization and CN bond cleavage to produce indenone derivatives.
DIRECT CONVERSION OF PHENOLS INTO AMIDES AND ESTERS OF BENZOIC ACID
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Page/Page column 15; 21, (2011/10/12)
A method is provided for the preparation of an aromatic carboxylic acid aryl ester or an N-aryl aromatic carboxamide. The method comprises contacting an O,O-diaryl thiocarbonate or an O-aryl-N-aryl thiocarbamate with a reactant that regioselectively reacts with sulfur, which contact causes an O-neophyl rearrangement, thereby forming either the aromatic carboxylic acid aryl ester or the N-aryl aromatic carboxamide, respectively.
Radical OfC transposition: A metal-free process for conversion of phenols into benzoates and benzamides
Baroudi, Abdulkader,Alicea, Jeremiah,Flack, Phillip,Kirincich, Jason,Alabugin, Igor V.
, p. 1521 - 1537 (2011/06/11)
We report a metal-free procedure for transformation of phenols into esters and amides of benzoic acids via a new radical cascade. Diaryl thiocarbonates and thiocarbamates, available in a single high-yielding step from phenols, selectively add silyl radicals at the sulfur atom of the CdS moiety. This addition step, analogous to the first step of the Barton-McCombie reaction, produces a carbon radical which undergoes 1,2 OfC transposition through an O-neophyl rearrangement. The usually unfavorable equilibrium in the reversible rearrangement step is shifted forward via a highly exothermic C-S bond scission in the O-centered radical, which furnishes the final benzoic ester or benzamide product. The metal-free preparation of benzoic acid derivatives from phenols provides a potentially useful alternative to metal-catalyzed carbonylation of aryl triflates.
Metal-free transformation of phenols into substituted benzamides: A highly selective radical 1,2-O→C transposition in O-aryl-N-phenylthiocarbamates
Baroudi, Abdulkader,Flack, Phillip,Alabugin, Igor V.
supporting information; experimental part, p. 12316 - 12320 (2010/12/29)
Radical merry-go-round: A highly efficient metal-free transformation of phenols into benzamides is designed through one-step conversion of phenols to aryl thiocarbamates and a subsequent radical addition/rearrangement/ fragmentation cascade. Computational analysis fully rationalizes the experimentally observed selectivity. Despite the possible competition from N-C fragmentation and N-neophyl rearrangement, the transformation exclusively follows the most kinetically and thermodynamically favored O-neophyl rearrangement path.
Phenyl chloro(thionoformate): A new dealkylating agent of tertiary amines
Milan, David S.,Prager, Rolf H.
, p. 841 - 849 (2007/10/03)
Phenyl chloro(thionoformate) reacts rapidly with unhindered tertiary aliphatic amines at 20° to give a thiocarbamate and an alkyl chloride. Dialkylcyclohexylamines react surprisingly rapidly to form predominantly cyclohexene. The thiocarbamates are converted into the secondary amine salt by treatment with dimethyl sulfate, followed by hydrolysis with water. Rates of reaction and alkyl group cleavage selectivity in amines were found to be superior or comparable to those previously reported with chloroformates.
The dealkylation of tertiary aliphatic amines with phenyl chlorothionoformate
Millan, David S.,Prager, Rolf H.
, p. 4387 - 4390 (2007/10/03)
Phenyl chlorothionoformate reacts reacts rapidly with aliphatic amines at 20°C to give a thiourethane and an alkyl chloride. The urethanes are readily converted to the secondary amine salt by reaction with dimethyl sulfate, followed by hydrolysis with wat
The chemistry of 5-oxodihydroisoxazoles. Part 22. The synthesis of 1,3-oxazin-6-ones from N-thioacylisoxazol-5(2H)-ones
Millan, David S.,Prager, Rolf H.
, p. 3245 - 3252 (2007/10/03)
N-Thioacylisoxazol-5(2H)-ones, prepared by the reaction of thiocarbonyl chlorides with isoxazol-5(2H)-ones in the presence of base, are reduced by triphenylphosphine to afford 1,3-oxazin-6-ones and triphenylphosphine sulfide. If the thioacylation is carried out with phenyl chlorodithioformate, the thermal rearrangement of the intermediate, to again form the oxazin-6-one and sulfur, is so rapid that the use of the phosphine is not required. The presence of an ethoxycarbonyl group at C-3, or of a bromine atom at C-4 of the isoxazolone results in the formation of thiazoles.
Imidazole-Assisted Intramolecular Phenoxythiocarbonylation of Tertiary Alcohols. A Key Reaction for the Deoxygenation of α-Trifluoromethylarylmethyl Alcohols
Hsu, Fu-Lian,Zhang, Xiaoyan,Hong, Seoung-Soo,Berg, Frederic J.,Miller, Duane D.
, p. 801 - 810 (2007/10/02)
The deoxygenation of α-trifluoromethylarylmethyl alcohols failed under catalytic hydrogenation conditions.However, these alcohols can be deoxygenated via their thionocarbonate intermediates followed by homolytic reductive cleavage of the C-O bond.The formation of the phenyl thionocarbonate esters is sterically dependent.Consequently, secondary α-trifluoromethyl arylmethyl alcohols can be smoothly converted to thionocarbonates, but tertiary alcohols cannot.Exceptions to this lack of reactivity are the aryl 4-substituted imidazolyl trifluoromethyl carbinols, which do form the thionocarbonates under these conditions.
Directed ortho metalation of O-aryl and O-pyridyl thiocarbamates. A versatile synthetic method for substituted phenol into thiophenol conversion
Beaulieu,Snieckus
, p. 112 - 118 (2007/10/02)
The preparation of ortho-substituted O-aryl and O-pyrid-3-yl thiocarbamates 7a-h and 11a-d and anionic ortho-Fries rearrangements of selected cases [O-phenyl N,N-diethylthiocarbamate (6a) → N,N-diethyl-2-hydroxy-3-methylbenzenecarbothioamide (9), O-[4-(tr
