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Boranes, tri

Biphenylcarboxylic acid [[1,1 -Biphenyl] -2-carboxylic acid], 83 Boron tnfluonde, etherate, [Borane, tri-fluoro-, compd. with l,l -oxybis-[ethane] (11)], 10 Bromine, 108... [Pg.139]

Dimethylamine (8) Methanamine, N-methyl- (9) (124-40-3) Tris(dimethylamino)borane Borane, tris(dimethylamino)- (8) Boranetriamine, hexamethyl- (9) (4375-83-1)... [Pg.185]

Borane Tris-[4-11 uoro-pbellyI]- ElOa. 258 (Educt)... [Pg.722]

For sodium cyanoborohydride — hydrogen chloride reagent the direction of the reductive opening of the dioxolane acetals obeys the same rule, it depends on the stereochemistry at the asymetric, benzylidene acetal carbon [168, 169]. Methyl exo-2,3 4,6-di-0-benzylidene-a-D-mannopyranoside is cleaved in oxolane solution to give 50 % of the 3,6-di-O-benzyl derivative, which is also the major product in the reaction of methyl 3-0-benzyl-4,6-0-benzylidene-a-D-mannopyranoside. The 2-O-benzyl isomer (20) was cleaved nonselectively, indicating again the effect of the bulk of the C-3 substituent [169]. A compatibility of this reagent, as well as of borane — tri-... [Pg.227]

Boran Tris-[(brom-dimethy]-silyl)-methyl]- XIII/3a, 296... [Pg.687]

Boran Tris-[3-chlor-2-methyl-propyl]- XIII/3a, 254... [Pg.1078]

Boran Tris-[tert.-butylperoxyJ-VI/2,232/E13/I,239f.(ausBCl3),... [Pg.1085]

For instance, attempts at isolating donor-free alkynylboranes have been hampered by spontaneous polymerization. The first donor-free tris(alkynyl)borane, tris(3,3-dimethyl-l-butynyl)borane (30), has only recently been obtained by reaction of deprotonated 3,3-dimethyl-l-butyne with boron trichloride at —78°C in pentane (equation 32). The alkynylborane (30) was fully characterized by multinuclear NMR spectroscopy, mass spectrometry, and X-ray crystallography. The NMR signal of (30) shows a remarkable shift of 5 = 48, which is upfield from typical shifts of alkyl-and alkenylboranes. The crystal structure of (30) shows similar C-C bond lengths, but significantly shorter B-C bonds in comparison to those observed for the donor-stabilized complexes (30) D indicative of a small degree of p - p interactions between the sp -boron atom and the sp-hybridized carbon. Weak r-overlap was further confirmed by ab initio calculations. It is this r-interaction that has been exploited for the development of nonlinear optical (NLO) materials based on alkynylboranes as described in Section 7.1. ... [Pg.488]

See other pages where Boranes, tri is mentioned: [Pg.11]    [Pg.593]    [Pg.11]    [Pg.489]    [Pg.130]    [Pg.133]    [Pg.245]    [Pg.263]    [Pg.309]    [Pg.309]    [Pg.334]    [Pg.334]    [Pg.336]    [Pg.672]    [Pg.684]    [Pg.1022]    [Pg.1085]    [Pg.1090]    [Pg.11]    [Pg.897]    [Pg.111]    [Pg.111]    [Pg.11]   


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Tris borane

Tris boranes

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