Clinicostatistical Study on Urinary

Ishikawa, Kiyoshi; Yamamoto, Masaru

doi:10.2185/jjrm.32.42

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“…We assume that the lone pair at the C atom of the anion [CRR'Br] ± or at the a-N atom of RN 3 attacks 1 a, followed by the elimination of Br ± or N 2 , respectively. We now found out that 1 a does not react with the silylene SiMe 2 , generated by the photolysis of the cyclohexasilane Si 6 Me 12 , when a solution of 1 a and Si 6 Me 12 is irradiated with UV light [26]. But 1 a does react, when R 2 SiCl 2 (R = tBu) is added together with lithium.…”

Section: Addition Of Sitbu 2 To 1 Amentioning

confidence: 87%

Reactions at the B-B Bond of Tri-tert-butylazadiboriridine NB2R3: Ring Extensions

Luckert¹,

Eversheim²,

Englert³

et al. 2001

Z. anorg. allg. Chem.

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The OCO carboxylate unit of pivalic acid adds to the B±B bond of the azadiboriridine NB 2 R 3 (1 a, R = tBu) to give the chiral heterocyclohexadiene 2 a; the enantiomers of 2 a are transformed into one another by a [1,3] sigmatropic hydride transfer along the B±N±B ring fragment. The azadiboracyclopentanes 3 a±e are formed from 1 a and the alkenes ethene, propene, isobutene, (trimethylsilyl)ethene, and 2,3-dimethyl-1-butene. Only one double bond of cyclopentadiene and 1,3-butadiene reacts in the same way to give 3 f, g, respectively, and both of the double bonds of 1,3-butadiene react with an excess of 1 a to give 3 h, which is obtained in a 9 : 1 mixture of racemate and meso-isomer; the meso-isomer crystallizes in the space group P2 1 /n. The corresponding diazadiboracyclopentane 3 i and the triazadiboracyclopentane 3 j are formed from 1 a and N-phenyl benzaldimine or azobenzene, respectively. Ethyne and 1 a give either the azadiboracyclopentene 4 a (1 : 1) or the diazatetraborabicyclo-[3.3.0]octane 3 k (1 : 2). The phosphaalkyne PºC±tBu and 1 a analogously yield the heterocyclopentene 4 c. The insertion of SitBu 2 into 1 a to give the azasiladiboracyclobutane 5 a is achieved by applying Li powder and tBu 2 SiCl 2 . The hitherto unknown azadiboriridines BN 2 R 2 R' (R = tBu; R' = 1-iPr, 2-Mes, 2-CMe 2 Et: 1 b±d) were synthesized by the chloroboration of the iminoboranes RBºNiPr and RBºNR with RBCl 2 , MesBCl 2 , and (EtMe 2 C)BCl 2 , respectively, and subsequent dechlorination of the isolated and characterized diborylamines Cl±BR±NiPr±BR±Cl (6 a), Cl±BR±NR± BMes±Cl (6 b), and Cl±BR±NR±B(CMe 2 Et)±Cl (6 c), respectively, with lithium (Mes = mesityl).The azadiboriridine 1 b dimerizes to give the diaza-nido-hexaborane 7 a, whereas 1 c and 1 d are storable at room temperature. The product 1 c crystallizes as a racemate in the space group P2 1 /c; its ring geometry differs from that of the known N-mesityl isomer.Reaktionen an der B±B-Bindung von Tri-tert-butylazadiboriridin NB 2 R 3 : Ringererweiterungen Inhaltsu È bersicht. Die OCO-Carboxylateinheit der Privalinsa È ure addiert sich an die B±B-Bindung des Azadiboriridins NB 2 R 3 (1 a, R = tBu) unter Bildung des chiralen Heterocyclohexadiens 2 a; die Enantiomeren von 2 a gehen durch [1,3]-sigmatropen Hydridtransfer entlang dem B±N±B-Ringfragment ineinander u È ber. Die Azaboracyclopentane 3 a±e entstehen aus 1 a und den Alkenen Ethen, Propen, Isobuten, (Trimethylsilyl)ethen bzw. 2,3-Dimethyl-1-buten. Je eine Doppelbindung von Cyclopentadien und 1,3-Butadien ergibt mit 1 a die Azadiboracyclopentane 3 f, g, und beide Doppelbindungen von 1,3-Butadien reagieren mit 1 a im Verha È ltnis 1 : 2 zu 3 h ab, das als 9 : 1-Mischung aus Racemat und mesoForm anfa È llt; das meso-Isomer kristallisiert in der Raumgruppe P2 1 /n. N-Phenylbenzaldimin und Azobenzol bilden mit 1 a das Diazadiboracyclopentan 3 i bzw. das Triazadiboracyclopentan 3 j. Die 1 : 1-Reaktion von 1 a und Ethin erbringt das Azadiboracyclopenten 4 a und die 2 : 1-Reaktion das Diazatetraborabicyclo[3.3.0]octan 3 ...

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Section: Addition Of Sitbu 2 To 1 Amentioning

confidence: 87%