Geometry optimization of the ring-opened oxirane diradical: mechanism of the addition reaction of the triplet oxygen atom to olefins

✍ Scribed by Kizashi Yamaguchi; Satoshi Yabushita; Takayuki Fueno; Shigeki Kato; Keiji Morokuma

• Publisher: Elsevier Science
• Year: 1980
• Tongue: English
• Weight: 338 KB
• Volume: 70
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(80)80053-4

✦ Synopsis

Geometry

optimmtlons of several low-lying tiadxal states of the ringapened ovirane (-CHZCH~O-) were performed by usmg the energy gradients of the UHF MIND0/3, STOJG and 4-31G solutions. Both the STO-3G and 4-3LG methods preduct that the most stable form IS the trlplet state of the non-tw&ed (IX conformation m which the unpaired spinslocaked on the termmal carbon and oxygen atoms are orlented perpendicularly to each other. The smglet uu dicadical state in which both the radxal-slte p orbltals are coplanar with the molecular framework IS only 2.3 (STO-3G) and 1.2 (4.31G) kcal/moI less stable than the triplet on duadxal state. It IS found that the geometry of the singlet oo diradical is unique in that the C-C-O angle IS notIceably small as compared wvlth various other duadlcal states. Imphcations of these results to the mechamsm of the oxuane-forming 0(3P) + CzH4 reactlon are dlscussed.