176 Proceedings of the Royal Irish Academy. 



chloroform solution was concentrated and alcohol was added. The separated 

 solid consisted mainly xrf the short prisms of the /3 compound, very similar 

 to cubes in appearance, with some prisms having pyramidal ends, which 

 probably consisted of unchanged a compound. 



A chloroform solution of the )3 isomeride when similarly treated gave 

 mainly unchanged j3 dibenzylidene-diacetoresorcinol. Inoculation of a 

 saturated solution of the a compound in chloroform and alcohol with crystals 

 of the /3 compound did not convert the a compound into the /3 form ; nor 

 conversely were we able to change the /3 form into the o isomeride by 

 inoculation of a saturated solution of the former with crystals of the latter. 



— O . OC . CH : CH . C 6 H 5 

 5. Resorcinol-dieinnamatc C c Hj 



— . OC . CH : CH . C 6 H, 



While seeking for a convenient method of preparing dibenzylidene- 

 diaeetoresorcinol we combined einnamoyl chloride with resorcinol in the hope 

 that the dicinnamate by interaction with zinc chloride or aluminium chloride 

 would give the desired compound. 



Cinnamic acid (30 grammes) and thionyl chloride (18 ces.) were heated in 

 a round flask under a reflux condenser until fumes ceased to be evolved. The 

 excess of thionyl chloride was then removed by distillation, and to the 

 residue, which consisted of einnamoyl chloride, 11 grammes of resorcinol and 

 16 grammes of pyridine were added. The mixture was heated in an oil-bath 

 to 120° C. for half an hour. The product was cooled, washed first with dilute 

 hydrochloric acid, afterwards with dilute sodium bicarbonate, and finally with 

 water and alcohol. 



After recrystallization from boiling alcohol about 35 grammes of resorcinol- 

 dicinnamate were obtained. 



When dried at 110 c C, it melted at 122-124° C, and gave on analysis the 

 following results : — 



01580 substance gave 0-4482CO, and 0-0723H.O, 

 corresponding to I 77 - 4 H51, 



C M H,A requires C 77"S4 H4S6. 



ResorciiwLdicinnamate crystallizes in colourless prisms which are sparingly 

 soluble in alcohol, soluble in ether or benzene, very soluble in chloroform, and 

 scarcely soluble in ligroin. 



Ferric chloride gives no coloration with a solution of the substance in 

 boiling alcohol. 



The percentage composition of the substance is nearly the same as that 

 of cinnamic anhydride ; and as we were unable to convert it by heating with 



