Reactions of aliphatic aldehydes under electron‐impact

Meyerson, Seymour; Fenselau, Catherine; Young, John L.; Landis, William R.; Selke, E.; Leitch, L. C.

doi:10.1002/oms.1210030602

Cited by 33 publications

(9 citation statements)

References 50 publications

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“…The mechanism in reaction 1 was postulated by Gilpin and McLafferty4 and that in reaction 2 by Meyerson at al. 7 The heat of reaction of (1) is 60 kJ mol'1. The heat of reaction of ( 2) is 63 kJ mol™1 by using Afff(vinyl alcohol) /ífívinyl alcohol) = -124 kJ mol-1 (from ref 25).…”

Section: Discussionmentioning

confidence: 99%

Field ionization kinetics. Unimolecular decomposition of the hexanal radical cation over the time range from 10 ps to 10 .mu.s

Derrick¹,

Falick²,

Lewis³

et al. 1979

J. Phys. Chem.

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Rates of formation of the major product ions from decomposition of hexanal, [3,3-2H2]hexanal, [4,4-2H2]hexanal, and [5,5-2H2]hexanal following field ionization have been determined over the time range 10 ps to several microseconds. These ions can be attributed to decomposition processes initiated by ß-, -, -, or e-hydrogen transfer to the oxygen via five-, six-, seven-, or eight-membered cyclic transition states. It is suggested that the McLafferty rearrangement at short times (<10-10 s) forms a vinyl alcohol ion and but-l-ene, and at longer times (10-10 to 10-6 s) a but-2-ene ion and vinyl alcohol. The observations at times <1 ns of m/e 57, m/e 73, and m/e 82 with [3,3-2H2]hexanal and m/e 73 with [4,4-2H2]hexanal are explained by decompositions initiated by /3-hydrogen transfer. The intermediate so formed rearranges by a 1,2-hydrogen shift to (CH= 0+,iHCH2C,sH1'HCTHCH2CH3), which then decomposes along its usual pathways (i.e., as if it were formed directly by -hydrogen transfer).

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Section: Discussionmentioning

confidence: 99%

Field ionization kinetics. Unimolecular decomposition of the hexanal radical cation over the time range from 10 ps to 10 .mu.s

Derrick¹,

Falick²,

Lewis³

et al. 1979

J. Phys. Chem.

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“…Other diagnostic ions are (M + -28), (M + -28 -18) and M + -44) due to the loss of ethylene, ethylene and water, and C 2 H 4 O. The mechanisms involved with this fragmentation have been discussed (Meyerson et al, 1970). The highly abundant ion with m/z 44 (CH 2 = CH-OH) + is a characteristic fragment only for aldehydes as a result of McLafferty rearrangement followed by β cleavage.…”

Section: Gc-ms Analysismentioning

confidence: 99%

Influence of diet upon the composition of pheromone volatiles inGalleria mellonella (greater wax moth) males

Ponomarev

Vendilo

Pletnev

et al. 1997

Arch. Insect Biochem. Physiol.

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“…21 The situation would be that of charge competition as discussed by Meyerson, et a!. 11 The analogous reactions in heptanal induced by FI have the same kinetic characteristics as the reactions in hexanal. 25 Here the IP of the 1-pentene molecule competing for the charge is 9.5 eV.…”

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confidence: 97%

“…Those 7-hydrogen rearrangements commonly referred to as McLafferty-type rearrangements have probably attracted more attention than any other rearrangement encountered in mass spectrometry;1 yet there is still considerable contention as to whether these ubiquitous rearrangements occur in a concerted or a stepwise manner.2-6 We have sought to elucidate this persistent question by applying the powerful capabilities of field ionization kinetics (FIK)7-9 to a study of two complementary 7-hydrogen rearrangements in hexanal.10'11 The FIK technique7-9 allows rates of unimolecular gas-phase reactions of (radical-) cations to be measured over a time range extending from [10][11][12] The hexanal-4,4-d2 species was studied so as to distinguish between transfer and transfer from other sites.14 There is no H/D randomization prior to fragmentation at 10""--9 sec (ref 14). It is evident from Figure 1 that the relative rates of these two reactions are sensitive functions of time.…”

mentioning

confidence: 99%

Mechanisms of unimolecular gas-phase .gamma.-hydrogen rearrangements of radical cations. Influence of entropy as opposed to energy

Derrick¹,

Falick²,

Burlingame³

1974

J. Am. Chem. Soc.

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SilacyclobutaneImine Benzene (mmol) (mmol) (mmol) ,---------Products (% yield^-------(CHz)&Me2 (21.2) PhCH=NPh (14.5) (59) (MezSiNPh)z (41) P h C H d H z (32) (CHz)3SiMe2 (13.2) Ph2CbNPh (5.20) ( 5 5 ) (MezSiNPhX (30) PhzCbCHz (56) PhzC=CHZ (33)b (CH&SiPhz (6.33) PhzC=NPh (3.03) (62) (PhzSiNPh)z (25)*+ aThese are based on the amounts of material actually isolated (either by preparative glpc or crystallization) and are probably 10-207$ lower than the quantities actually present. All reaction products are known compounds and, except as noted, were completely characterized by their ir and nmr spectra and, where applicable, melting points. * Calculated after correction for a 24% recovery of limiting reagent. Material was impure (mp 335-343", lit.6 mp 355.5"). Further recrystallization did not afford a purer sample.benzophenone (4.73 mmol), and benzene (66.7 mmol) afforded a homogeneous, yellow pyrolysate which, after resolution by preparative glpc afforded benzophenone phenylimine (0.79 mmol), styrene (0.78 mmol), 1,ldiphenylethylene (1.95 mmol), octamethylcyclotetrasiloxane (0.04 mmol), hexamethylcyclotrisiloxane (trace), benzophenone (1.74 mmol), and N-phenylbenzaldimine (12.7 mmol). Glpc analysis of the pyrolysate did not detect any 1,3-diphenyl-2,2,4,4tetramethylcyclodisilazane, (MezSiNPh)2. Isolation of benzophenone phenylimine provides definitive evidence for the formation of MezSi=NPh and its reaction with benzophenone since pyrolysis of equimolar quantities of either benzophenone and N-phenylbenzaldimine or benzophenone and (Me2SiNPh)z did not produce detectable quantities of this material. An explanation which accommodates all of these observations is outlined in Scheme 11. Assuming quantitative formation Scheme I1 --t [Me2Si=CH?I + CH?=CH? 3 G1l " Me,Si PhN=CHPh/ 1ph2C-0 + Ph,C=CH, + [Me2Si=O] PhCH =CH, + 1 [MelSi=NPh] -x+ (Me,SiNPh)? I Ph,C=Pu'Ph + [Me,Si=Ol of Me&=CHz and correcting, on the basis of the isolated yield of 1, 1-diphenylethylene, for the fact that 38.5 % of the MezSi=CH2 produced reacted with benzophenone, then the 0.79 mmol of benzophenone phenylimine isolated represents a 25.4 % yield of trappedMezSi=NPh. This is a minimum value since isolated yields were used and factors such as decomposition of the trapping reagents and products and other side reactions were ignored. The absence of significant side reactions and the relatively high yield of benzophenone phenylimine indicate that reaction schemes more complex than I1 are unlikely.The absence of (Me2SiNPh)z and the comparable quantities of styrene and benzophenone phenylimine observed indicate that benzophenone is a very efficient trapping reagent for silicon-nitrogen doubly bonded intermediates. This is in accord with our observationle that benzophenone is an excellent trapping reagent for intermediates containing silicon-carbon double bonds.Acknowledgment.

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Reactions of aliphatic aldehydes under electron‐impact

Cited by 33 publications

References 50 publications

Field ionization kinetics. Unimolecular decomposition of the hexanal radical cation over the time range from 10 ps to 10 .mu.s

Field ionization kinetics. Unimolecular decomposition of the hexanal radical cation over the time range from 10 ps to 10 .mu.s

Influence of diet upon the composition of pheromone volatiles inGalleria mellonella (greater wax moth) males

Mechanisms of unimolecular gas-phase .gamma.-hydrogen rearrangements of radical cations. Influence of entropy as opposed to energy

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