187940-18-7Relevant academic research and scientific papers
Application of 13C NMR Spectroscopy and 13C-Labeled Benzylammonium Salts to the Study of Rearrangements of Ammonium Benzylides
Zdrojewski, Tadeusz,Jończyk, Andrzej
, p. 452 - 457 (1998)
Ylides generated from N-(cyanomethyl)-N,N-dimethyl-N-[α-(trimethylsilyl)benzyl]ammonium chloride (4) and fluoride anion afford the products of [1,2] shift 11 and [2,3] shift 13. Formation of product 13 shows that, in the presence of water from TBAF, rearrangements and [1,3]H shift in ylide intermediates become competitive processes. The reaction of N-benzyl-N,N-dimethyl-N-[α-(trimethylsilyl)benzyl]ammonium bromide (5) and 13C labeled (at the benzyl carbon) salt 5* gave a mixture of 10, 14, and 15 as products of [1,4], [1,2], and [2,3] rearrangement, respectively. 13C NMR spectra of products derived from salt 5* exclude [1,3]H shift in ylide 9a+-. Rearrangement of ylides generated from N-benzyl-N,N-dimethyl-N-[(dimethylphenylsilyl)methyl]ammonium bromide (6*) (enriched in 13C at benzyl carbon) and n-BuLi reveals that N,N-dimethyl-2-[(dimeth-ylphenylsilyl)methyl]benzylamine (20*) is not formed by a [1,4] shift but instead, via a [2,3] shift in silylmethylide followed by subsequent [1,4]Si and [1,2]H shift, as previously suggested in the literature. This mechanism is unique to some silyl-substituted ylides.
Generation and reaction of benzylammonium N-methylides with N-cyanomethyl or N-(ethoxycarbonylalkyl) groups
Zhang, Chen,Maeda, Yasuhiro,Shirai, Naohiro,Sato, Yoshiro
, p. 25 - 28 (2007/10/03)
N-Cyanomethyl-, N-ethoxycarbonylmethyl- and N-(3-ethoxycarbonylpropyl)-N-methylbenzylammonium N-methylides 6a,b and 22 have been generated by fluoride ion-induced desilylation of the corresponding N-(trimethylsilylmethyl)benzylammonium salts 5a,b and 21. Sommelet-Hauser 7, 23 and Stevens 8, 24 rearrangement products were obtained from 6a and 22, but not from 6b.
New synthesis of β-aminoacid derivatives via hydroamination in Dimcarb
Hess,Dunkel,Muller
, p. 591 - 597 (2007/10/02)
A new selective hydro-dimethylamination method for unsaturated carboxylic acid derivatives with the pronucleophilic dimethylamine-precursor Dimcarb is described, which allows effective synthesis of hydro-β-dimethylamino-acid derivatives and unsaturated amides. Simple HMO quantum chemical calculation together with 1H NMR examination permits the prediction of suitable substrates, coupling position for dimethylamine as well as for mechanistical insights and optimal reaction course.
