ACIDITY OF DIBASIC ACIDS .1. THE 2ND ACIDITY CONSTANT OF 9,10-DIHYDRO-ANTHRACENE AND ITS 9,10-SUBSTITUTED DERIVATIVES - EFFECT OF SUBSTITUENT AND COUNTER ION
Io. Shapiro et al., ACIDITY OF DIBASIC ACIDS .1. THE 2ND ACIDITY CONSTANT OF 9,10-DIHYDRO-ANTHRACENE AND ITS 9,10-SUBSTITUTED DERIVATIVES - EFFECT OF SUBSTITUENT AND COUNTER ION, Perkin transactions. 2, (7), 1994, pp. 1519-1524
The second equilibrium ion pair acidity constants (pK2) of 9,10-dihydr
oanthracene, 9-phenyl-9,10-dihyroanthracene, 9,10-diphenyl-9,10-dihydr
oanthracene and 9-cyano-9,10-dihydroanthracene with sodium, potassium
and rubidium have been determined in tetrahydrofuran (THF) at 25-degre
es-C in the concentration range 10(-5)-10(-2) mol dm-3. Equilibria wer
e monitored by UV-VIS and H-1 NMR spectroscopies and the spectra of th
e dimetallic and monometallic salts reported. The dimetallic salts of
all the dibasic carbon acids studied behave as contact ion pairs in TH
F. The pK2 of 9,10-dihydroanthracene is insensitive to substituent eff
ect but is strongly dependent on the cation.