ISSN:
0030-493X
Keywords:
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
A detailed analysis of the mass spectral behavior of trialkylboranes and deuterium and 13C labeled tri-n-butylborane, and comparison with the ion cyclotron resonance behavior, have revealed several unique features and herefore unrecognized rearrangement and fragmantation reactions:(1)the occurrence of intial fragmentation of the parent ion with apparently nearly exclusive loss of one complete alkyl radical; (2) the extensive formation of boron-containing spiecies (〉% of the total ion current)in the mass spectrometer relative to the virtual absence (〈5%) of such spieces in the ion cyclotron resonance spectrum; (3) the dominant formation of boron-containing species of the composition [CnH2n+2B]+ with [C2H6B]+ generally being the base peak; (4) the formation of appreciable quantities of alkane molecular ions (5 to 10% of the total ion current) up to [R2]+. (from R3B); (5) the characterization of a fragmentation reaction involving the loss of CH2; (6) the observation that very extensive hydrogen and carbon scrmbling occurs in the ions formed after the initial fragmentation of the parent ion. A mechanism which satisfactorily accounts for the fragmentation and rearrangement reactions is proposed which involves the reversible formation and rearrangement of protonated boracyclopropanes and cyclopropanes formed by cationic insertions in ß-C—H bonds.
Additional Material:
12 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/oms.1210100308
