88454-98-2

Upstream product

• 88454-96-0 2-(2-{(1S,2S)-3-Benzyloxy-1-benzyloxymethyl-2-[2-(2-hydroxy-ethoxy)-ethoxy]-propoxy}-ethoxy)-ethanol 
• 88454-94-8 1,4-Di-O-benzyl-2,3-bis-O-<2-<2-(2-tetrahydropyranyloxy)ethoxy>ethyl>-L-threitol 
• 100-44-7 benzyl chloride 
• 68394-39-8 (2S,3S)-(-)-bis(dibenzyloxymethyl)-2,2-dimethyl-1,3-dioxolane 
• 88454-97-1 (7S,8S)-7,8-bis((benzyloxy)methyl)-1,14-dichloro-3,6,9,12-tetraoxatetradecane 

Downstream Products

• 88455-02-1 (2R,3R,11R,12R)-N,N,N'N'-Tetraoctyl-11,12-bis<(benzyloxy)methyl>-1,4,7,10,13,16-hexaoxacyclooctadecane-2,3-dicarboxamide 
• 88455-01-0 (2R,3R,11S,12S)-11,12-Bis-benzyloxymethyl-1,4,7,10,13,16-hexaoxa-cyclooctadecane-2,3-dicarbonyl dichloride 
• 88455-00-9 (2R,3R,11S,12S)-11,12-Bis-benzyloxymethyl-1,4,7,10,13,16-hexaoxa-cyclooctadecane-2,3-dicarboxylic acid 
• 88454-99-3 (2R,3R,11R,12R)-N,N,N',N'-Tetramethyl-11,12-bis<(benzyloxy)methyl>-1,4,7,10,13,16-hexaoxacyclooctadecane-2,3-dicarboxamide 

Relevant academic research and scientific papers

Synthesis of l-threitol-based crown ethers and their application as enantioselective phase transfer catalyst in Michael additions

A few new l-threitol-based lariat ethers incorporating a monoaza-15-crown-5 unit were synthesized starting from diethyl l-tartrate. These macrocycles were used as phase transfer catalysts in asymmetric Michael addition reactions under mild conditions to afford the adducts in a few cases in good to excellent enantioselectivities. The addition of 2-nitropropane to trans-chalcone, and the reaction of diethyl acetamidomalonate with β-nitrostyrene resulted in the chiral Michael adducts in good enantioselectivities (90% and 95%, respectively). The substituents of chalcone had a significant impact on the yield and enantioselectivity in the reaction of diethyl acetoxymalonate. The highest enantiomeric excess (ee) values (99% ee) were measured in the case of 4-chloro- and 4-methoxychalcone. The phase transfer catalyzed cyclopropanation reaction of chalcone and benzylidene-malononitriles using diethyl bromomalonate as the nucleophile (MIRC reaction) was also developed. The corresponding chiral cyclopropane diesters were obtained in moderate to good (up to 99%) enantioselectivities in the presence of the threitol-based crown ethers.

Synthesis of Lipophilic 18-Crown-6 Diacids for the Membrane Transport of Alkaline-Earth Cations

The synthesis of three different types of lipophilic 18-crown-6 diacids is described.A didecyl crown ether 2,3-diacid (1) was prepared as a minor product from a diiodide precursor (12) and threo-11,12-docosanediol by thallous ethoxide cyclization.The major nonpolymeric products resulted from elimination followed by cyclization to give 15-crown-5-derivatives.A crown ether 11,12-diamide 2,3-diacid (4) was prepared by a similar route involving cyclization of a benzyl protected precursor (26) and N,N,N',N'-tetramethyltartaramide (9).Isomeric syn and anti 2,11(12)-diamide 3,12(11)-diacid derivatives 6 and 7 were prepared from the known crown ether bisanhydride 8 and alkylamines.The product mixture was separated by chromatography, and the isomers were identified by comparison of acidity and stability constants for complexation with those of closely related syn/anti crown ether acids.