76697-97-7Relevant academic research and scientific papers
Unique zeolite-catalyzed synthesis of nitroketene S,N-acetals
Indrasena Reddy,Bhawal, Baburao M.,Rajappa, Srinivasachari
, p. 2101 - 2108 (2007/10/02)
Dimethyl carbonimidodithioates (4a-g, 7a-c) derived from various primary amines and amino acid esters [glycine, (L)-alanine and (L)-phenylalanine] have been condensed with nitromethane in the presence of the rare-earth exchanged zeolite RE(70%)Na Y to give the S,N-acetals (5a-g, 8a-c). Mercuric chloride catalyzed hydrolysis of these (8a-c) has led to the nitroacetyl derivatives (9a-c). The glycine derivative (7a) gives a dimeric product (11) when heated alone with the zeolite.
Metalated Nitrogen Derivatives of Carbonic Acid in Organic Synthesis, XV. - 2-Azaallyl Anions from Dialkyl N-(Benzyl)imidodithiocarbonates, -monothiocarbonates, and -carbonates as α-Benzylamine Anion Equivalents
Hoppe, Dieter,Beckmann, Ludger
, p. 1751 - 1764 (2007/10/02)
S,S'-Dimethyl N-(benzyl)imidodithiocarbonate (4a) was deprotonated by means of potassium tert-butoxide in THF or butyllithium in THF/HMPTA/hexane to give the 2-azaallyl anion 7a.Its alkylation yields mixtures of the α- and γ-substitution products 11a and 14a.In contrast, anion 7b, obtained from the S,S'-diethyl derivative 4b, is trapped by electrophiles predominantly in α-position, yielding 11b with high regioselectivity.Thus 4b constitutes a synthetic equivalent for α-metalated benzylamine 1.The less acidic O,O'-and O,S-dialkyl derivatives 5 or 6 were also dep rotonated and alkylated to give only α-adducts 12 or 13 via anions 8 or 9. - Lithium diisopropylamide under kinetic control predominantly abstracts a proton from an S-methyl group of 4a.The intermediate lithium compound 21 was trapped as silane 23 (besides 14aa). - Some further deprotonation experiments were also performed with the imino compounds 11aa, 11ab, 32a, and 32b in order to explore the scope of the metalation reaction.
