tion of the l tripeptide began: the small fraction was collected, which melted at 119.2-119.7°(lit.21 mp 116.5-119.5°). Continuous refrigeration gave more crystals of the same material. The residual peptide was obtained by reducing the volume of the solution amounting to 3.50 g, and about 0.26 g of oil was left uncrystallized: ir (

3-Amino-2-oxazolidones (7a-g) were prepared stereospecifically by condensation of 2-hydroxyalkylhydrazines (obtained by hydrazinolysis of the corresponding epoxides) with diethyl carbonate in the presence of sodium methoxide or by Namination of a 2-oxazolidone (7a,e,h-j). The appropriate oxazolidone was prepared either by condensation of a 2-hydroxyalkylamine, obtained by ammonolysis of an epoxide, with phosgene (10a) or A.A'-carbonyldiimidazole (10b), or by nitrosation of a /3-hydroxycarbohydrazide (13). Oxidation of 3-amino-2-oxazolidones with lead tetraacetate in Me2SO gave the 3-sulfoximino derivatives 14a-j. Except for 14h, these sulfoximines underwent smooth pyrolysis at <140 °C to yield MeaSO, CO2, N2, and an olefin. The latter was shown to be formed via a syn elimination from the sulfoximine 14, probably involving the diazene 4 as an intermediate. Application of this olefin synthesis to a preparation of bicyclo[3.3.1]non-l-ene led from keto ester 16 to exo sulfoximine 24 which, by a syn elimination, gave Z isomer 15a in an isolated 53% yield. Synthesis of endo sulfoximine 28, followed by pyrolysis (150 °C), afforded carboxylic acid 28. The latter is believed to be formed via the highly strained £-bicy-

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A variety of N-alkoxycarbonyl-TV.JVW-trialkylammonium fluoroborates have been synthesized from tertiary amines and alkyl chloroformates. The salts are stable and can be used in the mixed anhydride method of peptide synthesis. The yields of peptides are similar to those observed previously but the amount of racemization is apparently reduced as determined by the Anderson test. The salts also react readily with primary and secondary amines to give urethanes.