lenides 2 in 50-XOViO yields a s yellow oils. Selected spectroscopic data for 2f: 'HNMR(300MHz.CDCIJ:ii = 0.82(t.J=7.0Hz.bHj.1 65(dq.J=7.0,7.0 Hz, 4Hj. 2.2X Is, 2H). 4.76 (t. J =7.0 Hz. 2 H). 7.19 (dd. J = 7 5, 7.5 Hz, 2H). 7.33 (dd..~=~. S ,~. S H Z ,~H ) .~.~S (~. J =~.~H~.~H ) .~.~S (~. J =~S H~.~H ) :~~C N M R (75 MH7. CDCI,): 6 =10.3, 31.3. 74.7. 126.4, 128.3. 129.1. 130.0. 135.3. 146.5: "Se N M R (76 MHz, CDCI,): d = 456.1: [1]:" = + 262.0 ( c = I , CHCI,,): correct elemental analysis foi-C,,H,,0,Se2.Addition ofthe diselenides 2 to atyrene: 2 (0.1 nimol) was placed in dry diethyl ether (4 inL) under argon 'it -78°C and bromine (0.1 1 minol. 0.1 1 mL of a 1 M solutioii in CCI,) wis added. After 10 min silver triflate (72 mg. 0.28 minol) in methanol (0.1 mL) was added atid the mixture was stirred for 20 min at -78 ~ C. The reaction solution s a s cooled to -100 C and treated with styrene (0.4 mmol, 0.046 mL). After the mixture had been stirred Tor 2 h. .~~r~i.-colIidine (0.3 mniol, 0.04 inL) was added. ;ind the resultant mixture was heated to 20 C and washed with 7 % aqueous citric acid solution ( 5 mL). The organic phase was dried with MgSO,. and after remowl of the solwnt under vacuum. thc addition product 3 was purilied by column chroinatosraphy on silica (pentnne: rrrr-butylmethyl ether 3 : I ) . Selected apectroscopic data for 3f. 'H NMR (300 MHz. CDCI,): 6 = 0.98 (t. J =7.4 HL. 3H). 1.79 (quin,J =7.4H7. 2H). 2.41 (s. IH). 3.10-3 30(m. 2H). 3.24(s. 3Hj.4.36 (dd. J = 8 5. 5 HL. I H ) , 5.04 (in. 1Hj. 7.13-7.51 (m. 9H); "C NMR (75 MHz. 139.7. 133.7, 140 8. 140 0: correct elemental analysis Ibr C',,H,,O,Se.