Diphenylcyclopropenethione S-oxide

Abstract

products were separated by vpc. l-Phenyl-3,3-dimethylbutane: nmr (CDC13) 6 0.94 (s, 9, t-Bu), 1.50 (m, 2, RCHZR), 2.55 (m, 2, ArCHZR), and 7.20 (9, 5, phenyl); ir (film) 1370,1390 (unsym doublet, t-Bu), and 698, 733 em-' (C~HB); mass spectrum (75 eV) m/e (relative intensity) 162 (14) (Cl~H18+), 57 (100) ((AH9+). l-Phenyl-3,3-dimethylbutene: nmr (CDCls) 6 0.94 (8, 9, t-Bu), 6.24 (s, 2, vinyl), and 7.25 (m, 5, phenyl); ir (film) 1375, 1390 (unsym doublet, t-Bu), 975 (trans -CH=CH-), and 747, 694 em-' (-C6Hi); mass spectrum (75 eV) m/e (relative intensity) 160 (27) (CI%H~~+), 145 (100) (M+ -15), 91 (50) (C7H7+), and 57 (7) (C4Ho+).A repetition, using the products above in place of the p-bromostyrene, gave no change in the composition of the product, indicating that the olefin is not reduced by the organometallic.Reaction of Lithium Diphenylcopper with trans-and cis+ Bromostyrenes.-To a suspension of 5.2 g (0.027 mol) of cuprous iodide in 10 ml of ether at 0" was added 25 ml (0.055 mol) of commercial phenyllithium in 70: 30 benzene-ether:The solution was cooled to -78", and a solution of 1.0 g (0.0055 mol) of vpc-purified trans-@-bromostyrene in 10 ml of ether was added. The solution was stirred at -78" for 3 hr and then worked up in the usual way to give 1 .O g of a heavy oil containing large amounts of biphenyl and styrene (8070 of the mixture). The stilbene fraction (20y0) contained, by vpc analysis and isolation, using a 20y0 Apiezon L column, 1670 cis-stilbene, mp 4-7" (lit.* mp 5-6'), and 84% trans-stilbene, mp 124-125 (lit.9 mp 124").When the above reaction was repeated using vpc-purified cis-pbromostyrene, the stilbene fraction contained 7oY0 cis-and 30% trans-stilbene. RegistryNo.-LiCuR2, R = i-C3H7, 24012-11-1; LiCuRz, R = t-CdH9, 23924-63-2; LiCuR2, R = Ph,

4,5‐Dihydro‐1,2,3‐oxadiazole: A Very Elusive Key Intermediate in Various Important Chemical Transformations

“…We chose thallium(I) alkoxides13 as bases, because of their high solubility in various apolar solvents even at very low temperatures, which is quintessential for monitoring the reaction by NMR spectroscopy under such conditions. First, we utilized 2‐chloroethyl‐ N ‐nitrosourea ( 3 )4d as a substrate to investigate the formation of 1 in non‐aqueous solutions (Scheme ). Tosylate 4 was also synthesized for NMR studies, but it was not suitable owing to its limited solubility in dichloromethane at low temperatures.…”

Theoretical calculations of properties of some nitrosoureas

“…As such, water molecules gathered around it will stabilize the structure as compared to MNA. But even if the breaking of the parent molecule into the diazotates and the other segments does not occur via the transfer of the proton from N3 to 0 6 , still the loss of H1 from N3 remains a strong possibility [4] and as such is influenced by the substitutent on N3. Also, the stability of the ring depends on the charge on H1, and it seems likely that the ring prevents the inactivation of the compound by the plasma factor mentioned before.…”

“…An increased stability of the nitrosoureas when compared to nitrosamides can be imparted by their "Y-aromaticity ." Another consequence of the six -membered ring formation could be the possibility of intramolecular proton transfer, with H1 being abstracted by 0 6 as a step toward the formation of the diazotates which are the active species [4].…”

SV40 INDUCTION FROM A MAMMALIAN CELL LINE BY ULTRAVIOLET RADIATION and THE PHOTOSENSITIZERS 8‐METHOXYPSORALEN and ANGELICIN

“…One approach to the solution of this problem which has been used by several investigators is the use of angelicin, a furocoumarin considered unable to form crosslinks (Grant et al, 1979;Coppey et al, 1979;Kaye et al, 1980). Although crosslinking has been reported with angelicin, it appears to form monoadducts much more readily with less UV exposure (Lown and Sim. 1978 The purpose of this investigation was to determine whether t h e induction of SV40 from SV40transformed Syrian hamster kidney cells by 8-MOP + UV was the result of the formation of monoadducts or crosslinks.…”