Imidazolinone catalyst

March 1st, 2003, at the Eli Lilly Young Award symposium, Indianapohs. Their work was further communicated in >15 presentations in Europe, USA, Australia, and Asia prior to submission of their manuscript (October 10th, 2004) [132]) reported two more extensive protocols for the enantioselective conjugate reduction of o(,p-unsaturated aldehydes 47 and 51 using chiral imidazolinone catalysts 50 and 52. 

Propargyl alcohol (332) and (328) react readily with isocyanates in the presence of a basic catalyst to give 4-methylene-2-oxazolidinones (334) and 4-methylene-2-imidazolinones (336), respectively (63JOC991). In the absence of sodium methoxide the intermediate methanes (333) and ureas (335) were obtained and on treatment with sodium methoxide underwent ring closure. Moderate to excellent yields were obtained. 

Sheradsky has found that the hydroxyl function of a ketoxime such as acetophenone oxime can be made to react with DMAD when the reaction is carried out in methanol with a basic catalyst, to give mixture of the fumarate and maleate isomers (164) in the ratio 2 1. This mixture on heating undergoes a hetero-Cope rearrangement followed by cyclization and dehydration to give dimethyl 5-phenylpyrrole-2,3-dicarboxylate (168) (Scheme 25). Similarly, Heindel and Chun have reported that vinyl ether adducts (171), obtained by the condensation of arylamide oximes with DMAD, get thermally converted into oxa-diazolines (172) or imidazolinones (174), depending on the reaction conditions. A similar reaction occurs with aromatic amidoxime-methyl propiolate adducts to give imidazoles (170) (Scheme 26). 1,2,4-Dioxazoles have been reported to be formed in the reaction of hydrox-amic acids with DMAD. - ... 

Fig. 17 Bronsted acid-induced LLC phase formation of a chiral imidazolinone monomer as means of generating nanoporous, solid-state, chiral Diels-Alder catalysts. Partially reproduced with permission from [120]. 2005 by the American Chemical Society...

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