121459-16-3Relevant articles and documents
High α-regioselectivity in the rhodium-catalyzed hydroformylation of vinylpyrroles
Settambolo, Roberta,Caiazzo, Aldo,Lazzaroni, Raffaello
, p. 337 - 338 (1996)
The Rh4(CO)12-catalyzed hydroformylation at low temperature (40°C) of the 1-, 2- and 3-vinylpyrrole gives the corresponding branched aldehydes 2-(1-pyrrolyl)propanal, 2-(2-pyrrolyl)propanal and 2-(3-pyrrolyl)propanal with high α-regioselectivity.
Pyrrole-Protected β-Aminoalkylzinc Reagents for the Enantioselective Synthesis of Amino-Derivatives
Leroux, Marcel,Huang, Wan-Yun,Lemke, Yannick,Koller, Thadd?us J.,Karaghiosoff, Konstantin,Knochel, Paul
, p. 8951 - 8957 (2020)
Chiral β-aminoalkylzinc halides were prepared starting from optically pure commercial β-amino-alcohols. These amino-alcohols were converted to the corresponding N-pyrrolyl-protected alkyl iodides which undergo a zinc insertion in the presence of LiCl (THF, 25 °C, 10–90 min). Subsequent Negishi cross-coupling or acylation reactions with acid chlorides produced amino-derivatives with retention of chirality. Diastereoselective CBS-reductions of some prepared N-pyrrolyl-ketones provided 1,3-subsituted N-pyrrolyl-alcohols with high diastereoselectivity. Additionally, a deprotection procedure involving an ozonolysis allowed the conversion of the pyrrole-ring into a formamide without loss of optical purity.
Catalytic Hydrogenation of N-protected α-Amino Acids Using Ruthenium Complexes with Monodentate Phosphine Ligands
Saito, Akari,Yoshioka, Shota,Naruto, Masayuki,Saito, Susumu
supporting information, p. 424 - 429 (2019/11/28)
A ruthenium complex with a monodentate phosphine ligand was used to catalytically hydrogenate N-protected α-amino acids under essential retention of the configuration of their α-chiral centers. Among the ligands tested for this hydrogenation, which proceeds at a relatively low temperature, tris(para-fluorophenyl)phosphine exhibited the best performance. In comparison, electron-rich monodentate, bidentate, and tridentate phosphines were far less effective. The precatalyst Ru(OAc)2[(p-FC6H4)3P]2 was synthesized and isolated, and its structure was determined by a single-crystal X-ray diffraction analysis. N-protected α-amino acids with neutral alkyl side chains, including polar functional groups such as sulfides, indoles, ethers, phenols, pyrroles, and arenes, are compatible with the applied hydrogenation conditions, affording the corresponding optically active 2-substituted-2-(1H-pyrrol-1-yl)ethan-1-ol (2-amino ethanol) derivatives in moderate to high yield. (Figure presented.).
METHOD FOR PRODUCING ALCOHOL BY HYDROGENATION OF CARBOXYLIC ACID COMPOUND, AND RUTHENIUM COMPLEX FOR USE IN THE PRODUCTION METHOD
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Paragraph 0133; 0137; 0138, (2017/02/02)
PROBLEM TO BE SOLVED: To provide a method of obtaining an alcohol by efficiently hydrogenating a variety of carboxylic acid compounds under mild conditions using a homogeneous catalyst. SOLUTION: The present invention provides a method of hydrogenating a carboxylic acid compound, in the presence of a ruthenium complex represented by RuXnYpZq, in an atmosphere of hydrogen [X is a group represented by the following formula; Y is a phosphine ligand having a substituted/unsubstituted alkyl group or a substituted/unsubstituted aryl group; Z is a ligand other than X and Y; n is 1 or 2; p is an integer of 1-4; q is an integer of 0-2] {R1 is H, a substituted/unsubstituted alkyl group or a substituted/unsubstituted aryl group; A1 and A2 independently represent O, NR4 (R4 is H, a substituted/unsubstituted alkyl group or a substituted/unsubstituted aryl group) or S; m is an integer of 1 or more; a solid line and a dashed line both represent a single bond or a double bond}]. SELECTED DRAWING: None COPYRIGHT: (C)2017,JPOandINPIT
Nonenzymatic, enantioconvergent dynamic kinetic resolution (DKR) of racemic 2-(1H-pyrrol-1-yl)alkanoic acids as α-amino acid equivalents
Tokumaru, Eri,Tengeiji, Atsushi,Nakahara, Takayoshi,Shiina, Isamu
supporting information, p. 1768 - 1770 (2016/02/18)
We report an effective dynamic kinetic resolution (DKR) system of racemic 2-(1H-pyrrol-1-yl)alkanoic acids, which consists of a rapid racemization step via an activating substrate and an enantio-discriminating step via catalytic esterification. The combination of pivalic anhydride as an activating agent, bis(α-naphthyl)methanol as an achiral alcohol, (R)-BTM as a chiral acyl-transfer catalyst, and Hunig's base converted racemic 2-(1H-pyrrol-1-yl)alkanoic acids to the corresponding chiral carboxylates, which can be transformed into chiral α-amino acid derivatives with maintained high enantiopurity.
METHOD FOR MANUFACTURING ALCOHOL BY HYDROGENATION OF CARBOXYLIC ACID COMPOUND AND ESTER COMPOUND
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Paragraph 0117; 0118; 0127; 0129; 0132, (2016/10/10)
PROBLEM TO BE SOLVED: To provide a method for obtaining alcohol by hydrogenation of carboxylic acid compound efficiently by using a homogeneous system catalyst, especially a method for obtaining alcohol by hydrogenation of various carboxylic acid compound and ester compound by the homogeneous system catalyst efficiently even under alleviation condition. SOLUTION: A carboxylic acid compound and/or an ester compound is hydrogenated in a presence of a rhenium complex represented by ReXmYnZp, where X is a halogen atom, Y is same or different and each a ligand containing one or more phosphorus atom, Z is a ligand other than X and Y, m is an integer of 1 to 6, p is an integer of 0 to 2 and the sum of m, n and p is an integer of 2 to 6, and a specific alkali metal salt. COPYRIGHT: (C)2015,JPOandINPIT
New and clean synthesis of N-substituted pyrroles under microwave irradiation
Aydogan, Feray,Basarir, Mehmet,Yolacan, Cigdem,Demir, Ayhan S.
, p. 9746 - 9750 (2008/02/12)
N-Substituted homochiral pyrrole derivatives were synthesized by the ring-closure reaction of cis-1,4-dichloro-2-butene with various amine compounds on a silica surface under microwave irradiation.
