Arene-Mn(CO), cations react with the Schollkopf chiral glycine enolate equivalent (1) or (2) to give dien~l-Mn(C0)~ complexes which are converted to arylglycine methyl esters; the reaction sequence can be performed on aren~?-Mn(CO)~ complexes having protected amino acid substituents to give diaryl ethers having amino ester groups on both aromatic rings.We recently described a method for 0-phenylation of protected tyrosine and 4-hydroxyphenylglycine derivatives using a chlorobenzene-manganese tricarbonyl cation, which proceeded under very mild conditions and without detectable racemisation in the amino acid side chain.' If this chemistry can be developed to allow the construction of diaryl ethers having amino acid groups attached to both aromatic rings, it should provide access to subunits required for the synthesis of complex glycopeptide antibiotics such as vancomycin and ristocetin A,' as well as simpler peptides containing aryl ether linkages.3 We report herein our preliminary studies on the conversion of arene-Mn(C0)3 complexes to aryl glycines via their reaction with the Schollkopf chiral glycine enolate equivalent4 (I) or (2), which proceeds satisfactorily using arene-Mn(C0)3 systems having protected amino acid moieties in the side chain.Initial experiments utilised the simple arene-Mn(C0)3 complexes (3), which were treated with (1) [l equiv.
Coupling of (3-chloro-2-methylanisole)tricarbonylmanganese tetrafluoroborate with the phenoxide derived from methyl N-Boc-3-hydroxyphenylglycinate gave the diaryl ether manganese complex (6). This complex underwent regiospecific, stereoselective reaction with Schollkopf's chiral glycine enolate equivalent to give a mixture of dienyl-Mn(CO), complexes that were converted in a twostep sequence into the protected deoxyristomycinic acid derivative (1 2).* Acetonitrile has been used to effect decomplexation of arene-Mn(CO), complexes (refs. 5, 6, and 8). We observed that acetone also caused similar decomplexation, but at a slower rate.
Two lines of text have been omitted at the end of the first paragraph on page 132. The last sentence of this paragraph should therefore read 'In this paper, we report a novel photo-sensitized polymerization of pyrrole with the intention of directly forming a fine conducting ppy pattern on or in organic materials.'
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