A recent publication' demcribiug the reictiom of tetraDhenylcyclopentadieno& (tetracycloue) with a variety of tervalent phorphorur caapoundr prompts III to record soma of our ouu invertigetiona in thir field, which have led to new productr. Our initial interest vas aroused by the observation that a solution of tetracyclone in a dialkyl hydrogen Dhoaphonete (I; R = Me, Bt), containing about 10X of water, warn decolouriaed on heating. Addition of aquaour alcohol then gave the dihydro-cmpound (II)* (in veriable yield); the 888ignmnt of 4 rtereochmirtry to thir product, based on the mageitude of the coupling constant (JAB 2.5 ti) for the vicinal protona HA and llBI ir in agreement with other uorkerw.3 A possible mechanic for the formation of the dihydrocompound (II) is rhoun in Schem 1 (cf. ref. 1). It was conridered thet by using l trialkyl phorphite it right be porrible for an l lkyl group to be transferred to the five-mmbered ring, and indeed tctracyclone vith trimethyl phomphite in dichloromthane at mm-temperature for 2-3 days yielded 1,2,3,4-tetraphenylfulvone, together with a mixture of phomphter, l 0 found by Gallagher and Jeukius.'
*
To vhom all correspondence should be l ddrerred.