1- and 2-Naphthalenecarbonitriles (1- and 2-NN) photochemically react with 1,2,4,5,-tetramethylbenzene ( 4) (but not with lower homologues). The products are 1,1'-(1,2-ethane-diyl)bis-(2,4,5-trimethylbenzene) ( 5) and 3-hydroxy-1-naphthalenecarbontrile with 1-NN and 5 and 1,2-dihydro-2-naphthalenecarbonitrile with 2-NN. The reaction involves electron transfer to the NN singlet excited state followed by proton transfer. 4-Methylbenzyl-(1-cyano-4-naphthyl)methyl ether ( 9) and the corresponding trimethylbenzylderivative 10, which contain donor and acceptor chromophores linked together, were prepared and found to show enhanced excimer emission but no photochemical reactivity, 1- and 2-NN react with 1-methoxy-4-methylbenzene (but not with the 3-isomer) analogously as with 4, but in this case small amounts of benzylated 1,2-dihydro-1-naphthalenecarbonitriles and 1,4-dihydro-2-naphthalenecarbonitriles are also formed. The mechanism is discussed in comparison with the corresponding reaction of 1,4-naphthalenecarbonitrile.