[C-11]formaldehyde revisited: considerable concurrent [C-11]formic acid formation in the low-temperature conversion of [C-11]carbon dioxide into [C-11]formaldehyde

The reduction of [C-11]carbon dioxide with lithium aluminium hydride in die thyl ether at temperatures ranging from -56 degreesC to 19 degreesC was stu died. In contrast to what others have reported, considerable amounts of [C- 11]formic acid were found at all studied temperatures. (C) 2001 Elsevier Sc ience Ltd. All rights reserved.