Lithium 1-amino-l-

Carbohydrate-derived titanium cnolates also provide yvn-x-amino-/l-hydroxy esters of high diastcrcomeric and enantiomeric purity. For this purpose, the lithium enolate derived from ethyl (2,2,5,5-tetramcthyl-2,5-disilapyrrolidin-l-yl)acetate is first transmctalated with chloro(cy-clopentadienyl)bis(1,2 5,6-di-0-isopropylidene-a-D-glucofuranos-3-0-yl)titanium and subsequently reacted with aldehydes.. vj-n-a-Amino-/ -hydroxy esters are almost exclusively obtained via a predominant /te-side attack (synjanti 92 8 to 96 4 87-98% ee for the xvn-adducts)623-b. 

The thermal decomposition of some 3,5-disubstituted-l,2,4-thiadiazoles has been studied and some nonisothermal kinetic parameters have been reported <1986MI239>. Polarographic measurements of a series of methylated 5-amino-l,2,4-thiadiazoles show that thiadiazoles are not reducible in methanolic lithium chloride solution, while thiadiazolines are uniformily reduced at 0.5 = — 1.6 0.02 V. This technique has been used to assign structures to compounds which may exist theoretically as either thiadiazoles or thiadiazolines <1984CHEC(6)463>. The photoelectron spectrum for 1,2,4-thiadiazole has been published <1996CHEC-II(4)307>. 

Die analoge Reaktion von 3-Brom-propin mit Lithium-bis-[trimethylsilyl]-amid in Ether fuhrt zu 3-(Bis-[trimethylsilyl]-amino)-l-lithio-propin, das durch Zusatz von Elektrophilen (z.B. Aldehyden oder Ketonen) und nachfolgende Silylierung in stabile Produkte uber-gefuhrt werden kann, z.B. in l-(Bis-[trimethylsilyl]-ammo)-5-methyl-4-trimelhylsiloxy-2-hexin (53%)1. 

Sterisch gehinderte 1,3-Dialkyl-2-oxo-aziridine (a-Lactame) reagieren mit Alkyl- und Phenyl-lithium und auch mit 2-Lithium-l,3-dithian unter Bildung von (1-Amino-alkyl)-ketonen2,3 ... 

Alkyl-bromide (bzw. Allyl-bromid) sowie Ketone reagieren mit dem aus Benzophenon-methylimin und Lithium-diisopropylamid gebildeten l,l-Diphenyl-2-aza-allyl-lithium un-ter Substitution zu l-(Diphenylmethylen-amino)-alkanen bzw. l-(Diphenylme-thylen-amino)-2-hydroxy-alkanen, deren saure Hydrolyse 1-Amino-alkane bzw. 1-Ami no-2-hydroxy-alkane ergibt1. 

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