Pyrrolidinyl ethanol

Formation of ring-fused systems by this procedure is not as common. If the vicinally substituted hydroxyamino derivative is available, then Pb(OAc)4 treatment will lead to a ring-fused oxazole as in the conversion of (272) into (273) (71JCS(C)1482). In a different approach the CH=N— functional group is generated in situ. The 2-(l-pyrrolidinyl)ethanol... 

The most successful modifier is cinchonidine and its enantiomer cinchonine, but some work in expanding the repertoire of substrate/modifier/catalyst combinations has been reported (S)-(-)-l-(l-naphthyl)ethylamine or (//)-1 -(I -naphth T)eth Tamine for Pt/alumina [108,231], derivatives of cinchona alkaloid such as 10,11-dihydrocinchonidine [36,71], 2-phenyl-9-deoxy-10, 11-dihydrocinchonidine [55], and O-methyl-cinchonidine for Pt/alumina [133], ephedrine for Pd/alumina [107], (-)-dihydroapovincaminic acid ethyl ester (-)-DHVIN for Pd/TiOz [122], (-)-dihydrovinpocetine for Pt/alumina [42], chiral amines such as 1 -(1 -naphtln I)-2-(I -pyrro 1 idiny 1) ethanol, l-(9-anthracenyl)-2-(l-pyrrolidinyl)ethanol, l-(9-triptycenyl)-2-(l-pyrrol idi nyl)cthanol, (Z )-2-(l-pyrrolidinyl)-l-(l-naphthyl)ethanol for Pt/alumina [37,116], D- and L-histidine and methyl esters of d- and L-tryptophan for Pt/alumina [35], morphine alkaloids [113],... 

The enamine 3-(l-pyrrolidinyl)benzofuran (105, Scheme 26), reacts with a, -unsaturated ketones (106) in boiling benzene to produce the adducts 107, which on exposure to an ethanolic acetate buffer at room temperature provide the tetrahydro-2-dibenzofuranones 108. ... 

Minder et al. studied various modifiers containing a nitrogen base for the enantioselective hydrogenation of ethyl pyruvate.223,224 Up to 82% ee with (R)-l-(l-naphthyl)ethylamine and up to 75% ee with (/ )-2-( 1 -pyrrolidinyl)-1 -(1 -naphthyl)-ethanol as modifiers were achieved in the hydrogenation of ethyl pyruvate to (R)-ethyl lactate over Pt-Al203 in acetic acid. 

Kidwai et al. (2003) synthesized 4,6-diaryl-2-(4-morphohnyl/l-piperidinyl/l-pyrrolidinyl)pyrimidines by nucleophilic substitution reaction of substituted chal-cones, S-benzylthiuronium chloride (SBT) and morpholine/piperidine/pyrrolidine in ethanol. The rate enhancement and high yield was attributed to the coupling of solvent-free conditions and microwaves. 

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