Sodium Borotritide NaB

The NaB H4 reduction of carbonyl compoimds is a standard procedure for the synthesis of [ 1- H]alcohols, most usefully in the presence of various other functional groups, as for the precursors to [ll- H]ABT-229 (172) , (85)-20-hydroxy[20- H]hepoxilin A3 methyl 

Acyl chlorides 176 and 177 have been reduced to primary alcohols containing two tritium equivalents, as with intermediates in the preparation of the glutamate-gated chloride channel modulator nodulisporic [ H]ethanolamide (22Ci/mmol, 1771 and the NADHiubiquinone oxidoreductase photoaffinitv probe 179 (4.7 Ci/mmol), respectively. 

Methyl esters have been reduced with sodium borotritide at room temperature or at elevated temperature, providing an alternative to the less readily available and less stable LiAl H4 for the preparation of doubly labeled primary alcohols. High yields of products were reported for the reduction of ester 180 to the antitumor compound [ H]CEP-2563 (181). and of methyl benzyloxyacetate to give [ H2]alcohol 182. an intermediate in the preparation of the tritiated 5-HT2 antagonist deramciclane (183) ° . 

Reaction conditions 1. NaB H4 (10 equiv., 80 Ci/mmol), MeOH-THF 24 °C, 18 h (product 35.3 Ci/mmol) 2. NaB H4 (1.4 equiv, 633 mCi/mmol), MeOH-ferf-BuOH reflux, 1 h (product 221 mCi/mmol) 

EtOOC j NHFmoc EtOOC J NHFmoc EtOOC J NHFmoc 

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