J. Org. Chem., Vol. 39, iVo. 25, 1974 3799
Notes Anal. Calcd f o r C28H4&C, 87.88; H, 12.12. F o u n d C, 87.49; H, 12.45. 3-Deoxy-A -homovitamin DB (2). T h e photochemical apparat u s consisted o f a H a n o v i a q u a r t z immersion w e l l (Cat. N o . 19434) f i t t e d w i t h a 125-ml reaction vessel (equipped w i t h a condenser a n d nitrogen inlet) a n d a H a n o v i a 200-W medium-pressure mercury arc (Cat. No. 654A-36) w i t h a N o . 9700 Corex f i l t e r sleeve. T h e l a m p was prewarmed f o r 15 min before exposing t h e ice cooled reaction solution t o i r r a d i a t i o n f o r 3.0 min. T h e solution was purged thoroughly w i t h nitrogen p r i o r t o a n d d u r i n g t h e irradiation. F o u r i r r a d i a t i o n m i x t u r e s (125 m g o f 3/100 ml of ether each; 500 mg total) were pooled a n d concentrated a t
