piperonal + 1-nitropropane condensation

[Niels_Bohr]

Does anyone have an idea why the yield would be poor when reacting piperonal and 1-nitropropane (as reported by Shulgin under PIHKAL #94), and if anything can be done to get this condensation to work? 

[Rhodium]

Post 103792

(Rhodium: "Re: Piperonal ---> MDA", Chemistry Discourse)

[Nemo_Tenetur]

Several years ago i saw in the chemical abstracts an article from a russian researcher group. they claimed that a high-pressure condensation of piperonal and 1-nitropropane greatly increased the yield.

[Aurelius]

can you find that article?

[lugh]

Azafonov, N. E.; Sedishev, I. P.; Zhulin, V. M.
Bull.Acad.Sci.USSR Div.Chem.Sci.(Engl.Transl.) 1990, 39: 4.1 738-741
 Izv.Akad.Nauk SSSR Ser.Khim. 1990, : 4 829-832
The hitherto inaccessible nitroolefin (VII), which is the most convenient intermediate for the synthesis of the psychotropic amine (VIII), has been obtained by the direct condensation at high pressures (up to 1500 MPa) of piperonal (V) with 1-nitropropane (VI).The structure of (VII) was confirmed by direct synthesis from pyrocatechol (X).The amine (VIII) was obtained in three steps from (VII).This synthesis of (VIII) is shorter than that previously reported.

[Aurelius]

Lugh, you amaze aurelius sometimes.  You are truly great.