147898-97-3

Upstream product

• 67-56-1 methanol 
• 147700-73-0 (4R,5R)-4,5-bis[chloro(diphenyl)methyl]-2,2-dimethyl-1,3-dioxolane 
• 93379-48-7 (R,R)-TADDOL 
• 74-88-4 methyl iodide 

Relevant academic research and scientific papers

Asymmetric PTC C-Alkylation Catalyzed by Chiral Derivatives of Tartaric Acid and Aminophenols. Synthesis of (R)- and (S)-α-Methyl Amino Acids

A new type of efficient chiral catalyst has been elaborated for asymmetric C-alkylation of CH acids under PTC conditions. Sodium alkoxides formed from chiral derivatives of tartaric acid and aminophenols (TADDOL's 2a-e and NOBIN's 3a-h) can be used as chiral catalysts in the enantioselective alkylation, as exemplified by the reaction of Schiffs bases la-e derived from alanine esters and benzaldehydes with active alkyl halides. Acid-catalyzed hydrolysis of the products formed in the reaction afforded (R)-α-methylphenylalanine, (R)-α-naphthylmethylalanine, and (R)-α-allylalanine in 61-93% yields and with ee 69-93%. The procedure could be successfully scaled up to 6 g of substrate 1b. When (S,S)-TADDOL or (R)-NOBIN are used, the (S)-amino acids are formed. A mechanism rationalizing the observed features of the reaction has been suggested.

Catalytic asymmetric bromine-lithium exchange: A new tool to build axial chirality

We present here the first catalytic desymmetrization of the 2,2′,6,6′-tetrabromobiphenyl 1 and analogues, by a bromine-lithium exchange catalyzed by either diamines or diether derivatives (0.5 equiv.), yielding axially chiral compounds in high yield (up to 89%) and high enantioselectivity (up to 82%).

Asymmetric alkylation catalyzed by chiral alkali metal alkoxides of TADDOL. Synthesis of α-methyl amino acids

It is shown that sodium alkoxides formed from (4R,5R)-2,2-dimethyl-1,3-dioxolane-4,5-bis(diphenylmethanol) ((R,R)-TADDOL) and some of its derivatives can be used as chiral catalysts for enantioselective alkylation of Schiff's bases derived from alanine with reactive alkyl halides. Acid hydrolysis of the reaction products affords (R)-α-methytphenyl-alanine, (R)-α-allylalanine, and (R)-α-methylnaphthylalanine in 61-93% yields and with ee 69-94%. When (S,S)-TADDOL is used, the (3)-amino acid is formed. A mechanism explaining the observed features of the reaction is proposed.

TADDOLs on their way to late transition metal complexes - synthesis and crystal structure of N- and S-containing TADDOL-derived compounds

As a part of our research program aimed at the synthesis of TADDOL-derived ligands with heteroatoms other than oxygen as chelating units, we describe here new or improved routes to amino TADDOL-analogs (4, 5, 17-19, 21, 22, 26, 34 and 35) and thio-TADDOL-analogs (27-30 and 32).The sulfinato-thiolato Pt-complex 44 was prepared by an oxidative insertion of Pt into the S-S-bond of the corresponding thiosulfinate 29.Furthermore, the X-ray crystal structures of some of the new compounds (2-5, 28, 29, 32, 42 and 44) are presented and discussed. - Keywords: TADDOL derivative; chiral ligand; X-ray structure; platinum complex

Synthesis of (2R, 3R)-1,4-dimethoxy-1,1,4,4-tetraphenyl-2,3-butanediol: A new C2-symmetric vicinal diol from dimethyl L-tartrate

A practical synthesis of a new C2-symmetric vicinal diol, (2R, 3R)-1,4-dimethoxy-1,1,4,4-tetraphenyl-2,3-butanediol, from dimethyl L-tartrate involving five steps in overall yield of 38% is described.