Lithium cobalt phthalocyanine

The TCBOC group is stable to the alkaline hydrolysis of methyl esters and to the acidic hydrolysis of r-butyl esters. It is rapidly cleaved by the supemucleophile lithium cobalt(I)phthalocyanine, by zinc in acetic acid, and by cobalt phthalocy-anine (0.1 eq., NaBH4, EtOH, 77-90% yield). 

An experimental procedure for the conversion of iron(II) phthalocyanine into lithium methyl-(phthalocyanine)ferrate(II) can be found in Houben-Weyl, Vol. 13/9a, p 228. For analogous reactions involving cobalt, see Houben-Weyl, Vol. 13/9b, pp 55, 87. 

Protection of amino groups. Amino acids are converted to TCBpC-protected amino acids by reaction with 1 under the usual Schotten-Baumann conditions (80-95 7o yield). The products are nicely crystalline and are readily soluble in organic solvents. The TCBOC group is stable to N NaOH (40°, 2 hours) and to TFA (20°, 2 hours). The protecting group can be cleaved, as expected, with zinc in acetic acid or by reaction with lithium cobalt(I)-phthalocyanine. 

A reversible lithium-air system was first implemented on a laboratory scale in 1996. In this cell, the gel-polymer electrolyte was pressed between lithium foil on the one side and an air electrode on the other. (Later, usual liquid electrolyte in a porous, for example, glass fabric, separator was often used in lithium-air batteries). The whole cell was sealed into a plastic container ( coffee bag ) and small holes were made in the container wall adjacent to the air electrode to supply air under discharge and remove oxygen under charging. The air electrode was made of a mixture of particles of polymer electrolyte and carbon black with the catalyst supported on its surface (cobalt phthalocyanine). 

Abraham and Jiang were the first to report a lithium-oxygen organic electrol3Ae battery. The battery was shown to have an open circuit potential close to 3 V, an operating voltage of 2.0 to 2.8 V, and due to a cobalt phthalocyanine-catalyzed air electrode. 

Trahan MJ, Jia Q, Muktajee S, Plichta EJ, Hendrickson MA, Abraham KM (2013) Cobalt phthalocyanine catalyzed lithium-air batiraies. J Electrochem Soc 160(9) A1577—A1586... 

Deoxynucleosides have been protected at 0-5 by a modified dimethoxytrityl group as in 182 the A -hydroxysuccinimidyl ester permits attachment to resins with pendant amine groups, and the nucleoside can be recovered by mild acid treatment. On the other hand, the l,l-dianisyl-2,2,2-trichloroethyl ether (DATE) protecting group, as in 183, is particularly stable towards both acids and bases, but easily removed by reductive fragmentation using the supemucleophilic lithium cobalt(I) phthalocyanine. ... 

Cobalt (II) phthalocyanine is reduced by lithium benzophenone in tetrahydrofuran to lithium phthalocyanine cobaltate(I) (diamagnetic) and dilithium phthalocyanine cobaltate(O) (having one unpaired electron) (340). 

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