90831-19-9Relevant academic research and scientific papers
The Action of Sodium Nitrite-Acetic Acid on α- and β-Pinene. Participation by Neighbouring Geminal Dinitro Group in the Base-catalysed Epimerization of a Secondary Alcohol
Francisco, Cosme G.,Freire, Raimundo,Hernandez, Rosendo,Melian, Daniel,Salazar, Jose A.,Suarez, Ernesto
, p. 459 - 465 (2007/10/02)
The reaction of (-)-α-pinene (1) with sodium nitrite-acetic acid gave principally (2S,4R)-2-nitromentha-1(6),8-diene (2) and smaller amounts of (2S,4R)-2-nitromenth-1(6)-en-8-yl acetate (3), (1R,4S)-2-endo-nitrato-6-endo-nitrobornane (4), (1S,4R)--3,3-dimethyl-2-endo-nitrato-6-exo-nitro-8,9-dinorbornane (5), and (-)-3-nitropin-2-ene (6).A similar reaction with (-)-β-pinene (8) afforded (4S)-7-nitromentha-1,8-diene (9) as the major product and (4S)-7-nitromenth-1-en-8-yl acetate (10), (1S,4S)-2-endo-nitrato-10-nitrobornane (11), and (1R,4S)-3,3-dimethyl-2-endo-nitrato-10-nitro-8,9-dinorbornane (12) in lower yields.Treatment of the nitro-nitrates (11) and (12) in basic medium gave the corresponding 10,10-dinitro alcohols (20) anfd (21) by intramolecular transfer of the nitro group with retention of configuration at C-2.In stronger alkaline conditions the dinitro endo-alcohol (21) produced unexpectedly the epimeric exo-alcohol (22).The neighbouring participation of the 10,10-dinitro qroup is shown to be essential for the epimerization to take place.Plausible mechanisms for these reactions are proposed.
