Some of 9-aryl-9,10-dihydro-9-silaanthracenes (1) were prepared and the alkylation of the compounds gave trans-9-aryl-10-alkyl-9,10-dihydro-9-silaanthracenes exclusively. Upon photolysis of a 9-phenyl derivative, 9-phenyl-9-silaanthracene was confirmed by spectroscopic analysis. Also, structural studies of the dihydro compounds were performed by NMR and X-ray.