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3
was stored at À18 °C for 10 months, while storing
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(
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1
1
1. For a recent example, see: Li, X.-C.; Ferreira, D.; Jacob,
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2
3. Treatment of Me-GABA.HCl with aqueous NaHCO3
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325(a recent procedure); (b) Sorg, A.; Bru ¨ckner, R.
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synthesis).
Carbamate
salt
formation
2 3
(MeOCO(CH ) NH-
À
+
1
3. Cop e´ ret, C.; Sugihara, T.; Wu, G.; Shimoyama, I.;
Negishi, E. J. Am. Chem. Soc. 1995, 117, 3422–3431.
4. For the development of methodology, see: (a) Kotora, M.;
Negishi, E. Synthesis 1997, 121–128; (b) Rossi, R.; Bellina,
F.; Mannina, L. Tetrahedron Lett. 1998, 39, 3017–3020;
COO Na ) is the most likely reason for this observation;
for examples of the reaction of amines with CO giving
2
rise to carbamates, see e.g.; V a´ vrov a´ , K.; Hrab a´ lek, A.;
Dole zˇ al, P.; Holas, T.; Klimentov a´ , J. J. Contr. Release
1
2
005, 104, 41–49.