Reduction dimethyl itaconate

H-transfer reduction Investigated in Micro Reactors Organic synthesis 63 [OS 63] H-transfer reduction of dimethyl itaconate... 

Figure 4.78 Liquid/liquid H-transfer reduction of dimethyl itaconate to dimethyl methylsuccinate experimental results vs models.

Fu has reported a planar-chiral bisphosphorus ligand 45 with a phosphaferrocene backbone. The ligand has provided enantioselectivity up to 96% ee in the hydrogenation of a-dehydroamino acid derivatives.99 Another planar-chiral ferrocene-based bisphosphorus ligand 46 has been reported by Kagan recently and enantioselectivity up to 95% ee has been obtained in the reduction of dimethyl itaconate.100... 

In hydrogenations with H2 in D20 the product showed only CHD— stretches in the infrared. This observation excludes a fast H/D exchange on Pd, and implies a monohydridic mechanism of hydrogenation. With the same catalyst in an aqueous (D20) solution, itaconic acid is reduced under H2 to yield multiply deuterated methyl succinic acid having 1.97 deuterons at C3, 0.66 at C2 and none at Cl (Eq. 32) [83]. On the other hand, in an H20/ethyl acetate biphasic solvent mixture, the catalyst prepared in situ from [Rh(cod)Cl]2 and TPPTS catalyzed the reduction (with D2) of dimethyl itaconate with deuterium incorporation at C3 (2.06), C2 (0.78) and at Cl (0.18) [84], Similar results were obtained in toluene/methanol (1 1) with the Rh(I)-BPPM cationic catalyst [85], Again, these findings could be explained by a fast /3-elimination from the intermediate Rh(I)-alkyl. 

Our intended synthesis of this compound began with the Diels-Alder condensation between butadiene and dimethyl itaconate. The less congested carboxyl group of the diester product can be hydrolyzed selectively and converted to the aldehyde via reduction of the acid chloride with a cuprous borohydride derivative. ... 

The ferrocene-derived Josiphos ligands (137) first reported by Togni and Spindler [99] are another class of chiral diphosphine ligands that are of immense importance both in asymmetric hydrogenations and in other asymmetric transformations. A variety of substrates can be reduced with high enantioselectivity in the presence of chiral metal complexes derived from these ligands. The reduction of dimethyl itaconate (136) furnishes 138 in quantitative yield and 98-99 % ee (Equation 39) [99]. 

The synthesis of 4-carboxy-2-piperidone entailed addition of hydrogen cyanide to dialkyl itaconate, emd reductive cycliza-tion of the resulting dialkyl cyanomethyl succinate to 4-alkoxy-carbonyl-2-piperidone followed by saponification (7). The other member of this group, 4-c u boxy-2-pyrrolldone, was obtained from its methylester which was synthesized via esterification of amino methyl succinic acid (B). The 6,6 dimethyl-4-carboxy-2-plperidone was synthesized by reductive cyclization of methyl 3-methoxy-... 

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