- New fluorine-18 labeled benzaldehydes as precursors in the synthesis of radiopharmaceuticals for positron emission tomography
-
4,5-Bis(butoxy)-2-nitrobenzaldehyde and 4,5-bis(tert-butoxycarbonyloxy)-2-nitrobenzaldehyde, as well as their fluorine-18 labeled derivatives (the half-life of F18 is T1/2 = 110 min) were synthesized for use as precursors in the synt
- Orlovskaja,Fedorova,Studentsov,Golovina,Krasikova
-
-
Read Online
- Process for preparing 5,6-dihydroxyindole
-
5,6-Dihydroxyindole is prepared by the catalytic reductive cyclization of 4,5-dihydroxy-2,β-dinitrostyrene in a single step using hydrogen with a palladium, platinum or rhodium catalyst in a polar hydroxylic reaction system. No reaction byproducts or only a single reaction byproduct are produced. The 4,5-dihydroxy-2,β-dinitrostyrene intermediate can be prepared by the chemoselective debenzylation of 4,5-dibenzyloxy-2,β-dinitrostyrene using trifluoroacetic acid. 5,6-Dihydroxyindole is a useful component in hair dye formulations and as an intermediate in the synthesis of melanin.
- -
-
-
- SYNTHESIS OF 5,6-DIHYDROXYINDOLE: A NOVEL REDUCTIVE CYCLIZATION OF (E)-4,5-DIHYDROXY-2,β-DINITROSTYRENE
-
A unique catalytic reductive cyclization of (E)-4,5-dihydroxy-2,β-dinitrostyrene (1) to 5,6-dihydroxyindole (2) is reported.Compound 1 is obtained either by one-step CF3CO2H deprotection of 4,5-dibenzyloxy-2,β-dinitristyrene (7), or by an improved two-step demethylenation of 6-nitropiperonal (5), followed by condensation with CH3NO2.
- Murphy, Bryan P.,Banks, Harold D.
-
p. 321 - 330
(2007/10/02)
-
- Synthesis of 6-Aminoisoproterenol
-
A number of possible approaches to the ring-aminated isoproterenol derivative 4-ethyl>-5-amino-1,2-benzenediol have been attempted.Of these, the total synthesis using the commercially available starting material 6-nitrop
- Avery, Mitchell A.,Verlander, Michael S.,Goodman, Murray
-
p. 2750 - 2753
(2007/10/02)
-