The cyanomethyl radical H2CCN had been identified
in spectra recorded toward TMC-1 and Sgr B2 first by
W. M. Irvine, P. Friberg, Å. Hjalmarson, S. Ishikawa, N. Kaifu, K. Kawaguchi, S. C. Madden, H. E. Matthews, M. Ohishi, S. Saito, H. Suzuki, P. Thaddeus, B. E. Turner, S. Yamamoto, L. M. Ziurys,
Identification of the Interstellar Cyanomethyl Radical (CH2CN) in the Molecular Clouds TMC-1 and Sagittarius B2
Astrophys. J. 334, L107L111 (1988).
Some of these lines have been observed before and attributed to one unknown insterstellar molecule
S. E. Cummins, R. A. Linke, and P. Thaddeus,
A survey of the millimeter-wave spectrum of Sagittarius B2
Astrophys. J. 576, 819878 (1986).
Quite recently, H2CCN was among several molecules detected
with the IRAM 30 m telecope in the circumstellar envelope of
the carbon-rich AGB star CW Leo, aka IRC +10216:
M. Agúndez, J. P. Fonfría Expósito, J. Cernicharo, J. R. Pardo and M. Guélin,
Detection of Circumstellar CH2CHCN, CH2CN, CH3CCH, and H2CS
Astron. Astrophys. 479, 493501 (2008).