1145-80-8Relevant articles and documents
An alkylidene carbene C-H insertion strategy for the enantioselective synthesis of α,α-dialkyl-α-amino acids
Gabaitsekgosi, Renameditswe,Hayes, Christopher J.
, p. 7713 - 7716 (1999)
A synthesis of the α,α-dialkyl-α-amino acid (1S,3R)-2,5-methano-leucine has been achieved using an alkylidene carbene 1,5-C-H insertion reaction as a key step. Treatment of the ketone 11 with 1.2 equivalents of lithio(trimethylsilyl)diazomethane in THF resulted in the formation of the cyclopentene 13 in 62% yield. The enantiomeric excess of the product 18 was determined to be >95% by chiral HPLC (Chiracel OD column).
A Convenient Synthesis of Methyl 2-thazoline-4-carboxylate, an Important Skeleton of Cyclothiazomycin
Shin, Chung-gi,Ito, Akio,Okumura, Kazuo,Nakamura, Yutaka
, p. 45 - 46 (1995)
The convenient syntheses of a few methyl 2-(1-amino)alkenyl thiazoline-4-carboxylates and methyl 2-thiazoline-4-carboxylate have been accomplished.The latter is an important portial skeleton of macrobicyclic peptide antibiotic cyclothiazomycin.
Synthesis method and application of 1-aza -5-germanium-5-alkyl bicyclic [3.3.3] undecane compound.
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Paragraph 0216; 0221, (2020/05/11)
The invention provides a 1-aza-5-germanium hetero-5-alkyl bicyclic [3.3.3] hendecane compound having a structure shown in the formula I, and the types of the 1-aza-5-germanium hetero-5-alkyl bicyclic[3.3.3] hendecane compound are expanded. The provided compound can serve as a nucleophilic reagent, the air and humidity conditions of the nucleophilic reagent are stable, and the efficiency of the Ge-Stille coupling reaction of aryl halogen and the 1-aza-5-germanium hetero-5-alkyl bicyclic [3.3.3] hendecane compound is high.
Mild, Rapid, and Chemoselective Procedure for the Introduction of the 9-Phenyl-9-fluorenyl Protecting Group into Amines, Acids, Alcohols, Sulfonamides, Amides, and Thiols
Soley, Jacob,Taylor, Scott D.
, (2020/02/04)
The 9-phenyl-9-fluorenyl (PhF) group has been used as an Nα protecting group of amino acids and their derivatives mainly as a result of its ability to prevent racemization. However, installing this group using the standard protocol, which employs 9-bromo-9-phenylfluorene/K3PO4/Pb(NO3)2, often takes days and yields can be variable. Here, we demonstrate that the PhF group can be introduced into the amino group of Weinreb's amides and methyl esters of amino acids, as well as into alcohols and carboxylic acids, rapidly and in excellent yields, using 9-chloro-9-phenylfluorene (PhFCl)/N-methylmorpholine (NMM)/AgNO3. Nα-PhF-protected amino acids can be prepared from unprotected α-amino acids, rapidly and often in near quantitative yields, by treatment with N,O-bis(trimethylsilyl)acetamide (BSA) and then PhFCl/NMM/AgNO3. Primary alcohols can be protected with the PhF group in the presence of secondary alcohols in moderate yield. Using PhFCl/AgNO3, a primary alcohol can be protected in good yield in the presence of a primary ammonium salt or a carboxylic acid. Primary sulfonamides and amides can be protected in moderate to good yields using phenylfluorenyl alcohol (PhFOH)/BF3·OEt2/K3PO4, while thiols can be protected in good to excellent yield using PhFOH/BF3·OEt2 even in the presence of a carboxylic acid or primary ammonium group.
