N-Methylidene[bis(trimethylsilyl)methyl]amine: the first isolable and stable monomeric methanimine allowing thermal [2 + 2] cycloadditions with ketenes
N-Methylidene[bis(trimethylsilyl)methyl]amine: the first isolable and stable monomeric methanimine allowing thermal [2 + 2] cycloadditions with ketenes
Reaction of [bis(trimethylsilyl)methyl]amine with aldehydes, leads to Schiff bases with unexpected remarkable stability.
A Contribution to the Asymmetric Synthesis of 3-Amino β-Lactams: The Diastereoselective [2+2] Cycloaddition Reaction of Chiral Aminoketene Equivalents with Enolizable Aldehyde-Derived Imines
作者:Claudio Palomo、Jesus M. Aizpurua、Marta Legido、Antonia Mielgo、Regina Galarza
DOI:10.1002/chem.19970030909
日期:1997.9
AbstractN‐[Bis(trimethylsilyl)methyl]imines 9 show unique chemical properties when compared with conventional imines. Their reaction with optically pure aminoketenes derived from dehydrochlorination of 14 and 15 affords the corresponding 3‐amino‐4‐alkyl‐β‐lactams 16 and 17 in good yields and high diastereoselectivities. The mild deprotection of bis(trimethylsilyl)methyl‐ and phenyloxazolidinone moieties with, respectively, cerium(IV) ammonium nitrate and lithium/ammonia or hydrogen/Pd(OH)2 allows the preparation of a variety of β‐lactam antibiotic building blocks.
N-Methylidene[bis(trimethylsilyl)methyl]amine: the first isolable and stable monomeric methanimine allowing thermal [2 + 2] cycloadditions with ketenes
作者:Claudio Palomo、Jesus M. Aizpurua、Marta Legido、Regina Galarza
DOI:10.1039/a607348d
日期:——
N-Methylidene[bis(trimethylsilyl)methyl]amine acts as a stable
methanimine synthon [CH
2
NH] equivalent in [2 + 2]
cycloadditions to ketenes, generated from acid chlorides and
triethylamine, to provide 4-unsubstituted β-lactams in a single
step.