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1.
From a Si3‐Cyclopropene to a Si3S‐Bicyclo[1.1.0]butane to a Si3S‐Cyclopropene to a Si3S2‐Bicyclo[1.1.0]butane: Back‐and‐Forth,and In‐Between
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Dr. Vladimir Ya. Lee Dr. Olga A. Gapurenko Shogo Miyazaki Prof. Dr. Akira Sekiguchi Prof. Dr. Ruslan M. Minyaev Prof. Dr. Vladimir I. Minkin Prof. Dr. Heinz Gornitzka 《Angewandte Chemie (International ed. in English)》2015,54(47):14118-14122
Compact and highly reactive bicyclo[1.1.0]butanes constitute one of the most fascinating classes of organic compounds. Furthermore, interplay of bicyclo[1.1.0]butanes with their valence isomers, such as buta‐1,3‐dienes and cyclobutenes, is among the fundamental pericyclic transformations in organic chemistry. Herein we report the back‐and‐forth interconversion between the cyclotrisilenes and thiatrisilabicyclo[1.1.0]butanes, allowing for the synthesis of novel representatives of such classes of highly reactive organometallics. The peculiar structural and bonding features of the newly synthesized compounds, as well as the mechanism of their isomerization, were verified both experimentally and computationally. 相似文献
2.
The variability of carbon-carbon single bonds by steric and electronic effects is probed by DFT calculations of sterically crowded bicyclo[1.1.0]butanes and their radical cations. The interplay of sterics and electronics on the gradual weakening and breaking of bonds was studied by investigating bridgehead substitution in 1,3-di-tert-butylbicyclo[1.1.0]butane and 2,2',4,4'-tetramethyl-1,3-di-tert-butylbicyclo[1.1.0]butane and geminal substitution in 2,2'-di-tert-butylbicyclo[1.1.0]butane and 2,2',4,4'-tetra-tert-butylbicyclo[1.1.0]butane. Bridgehead substitution leads to a lengthening of the central bond, whereas bisubstitution on the geminal carbon leads to a shortening of this bond due to a Thorpe-Ingold effect. Although the character of the central bond can be modulated by substitution and electron transfer over a range of 0.35 A, the state forbidden ring planarization does not occur. Sterically crowded bicyclo[1.1.0]butane radical cations are therefore promising candidates for the investigation of extremely long carbon-carbon single bonds. 相似文献
3.
Lee VY Miyazaki S Yasuda H Sekiguchi A 《Journal of the American Chemical Society》2008,130(9):2758-2759
Group 14 and 16 hybrid heavy bicyclo[1.1.0]butanes (tBu2MeSi)4Si3E (E = S, Se, and Te) 2a-c have been prepared by the [1 + 2] cycloaddition reaction of trisilirene 1 and the corresponding chalcogen. Bicyclo[1.1.0]butanes 2 have exceedingly short bridging Si-Si bonds (2.2616(19) A for 2b and 2.2771(13) A for 2c), a phenomenon explained by the important contribution of the trisilirene-chalcogen pi-complex character to the overall bonding of 2. Photolysis of 2a and 2b produced their valence isomers, the heavy cyclobutenes 3a and 3b, featuring flat four-membered Si3E rings and a planar geometry of the Si=Si double bond. The mechanism of such isomerization was studied using deuterium-labeled 2a-d6 to ascertain the preference of the pathway, involving the direct concerted symmetry-allowed transformation of bicyclo[1.1.0]butane 2 to cyclobutene 3. 相似文献
4.
A. I. D'yachenko N. M. Abramova S. V. Zotova O. A. Nesmeyanova O. V. Bragin 《Russian Chemical Bulletin》1985,34(9):1885-1889
Conclusions A new general synthesis is proposed for bicyclo[1.1.0]butanes, by 1,3-cyclization of 1-bromo-chloromethylcyclopropanes, and a two-step synthesis of the latter from available allyl chlorides has been developed.Deceased.Translated from Izvestlya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2043–2047, September, 1985. 相似文献
5.
Guillaume Ernouf Egor Chirkin Lydia Rhyman Ponnadurai Ramasami Jean‐Christophe Cintrat 《Angewandte Chemie (International ed. in English)》2020,59(7):2618-2622
A new photoredox‐catalyzed decarboxylative radical addition approach to functionalized cyclobutanes is described. The reaction involves an unprecedented formal Giese‐type addition of C(sp3)‐centered radicals to highly strained bicyclo[1.1.0]butanes. The mild photoredox conditions, which make use of a readily available and bench stable phenyl sulfonyl bicyclo[1.1.0]butane, proved to be amenable to a diverse range of α‐amino and α‐oxy carboxylic acids, providing a concise route to 1,3‐disubstituted cyclobutanes. Furthermore, kinetic studies and DFT calculations unveiled mechanistic details on bicyclo[1.1.0]butane reactivity relative to the corresponding olefin system. 相似文献
6.
Takeaki Iwamoto Takashi Abe Kunihisa Sugimoto Daisuke Hashizume Hiroshi Matsui Ryohei Kishi Masayoshi Nakano Shintaro Ishida 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(13):4415-4419
Bicyclo[1.1.0]tetrasil‐1(3)‐ene 1 , a tetrasilicon analogue of bicyclo[1.1.0]but‐1(3)‐ene that contains a formal double bond between bridgehead silicon atoms in an inverted geometry, was synthesized and isolated in the form of thermally stable orange crystals. The distance between the bridgehead Si atoms in 1 is much longer than those in typical Si=Si bonds, but still shorter than that of a previously reported pentasila[1.1.1]propellane. DFT calculations suggest that the bridgehead bond in 1 comprises a σ bond with an inverted geometry and a π bond. This notion is supported by the UV/Vis spectrum of 1 , which exhibits several absorption bands in the UV/Vis region. While 1 is stable toward typical trapping agents for Si=Si double bonds, 1 reacts with carbon tetrachloride to furnish a hexachlorotetrasilane. 相似文献
7.
Conclusions A study was carried out on the electrophilic addition of some divalent mercury compounds to bicyclo[1.1.0]butane and a mechanism was proposed accounting for the ratio of cyclobutyl and cyclopropylcarbinyl products.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1080–1083, May, 1982. 相似文献
8.
Sterically congested 1‐azabicyclo[1.1.0]butanes 1 add hydrazoic acid smoothly at 0–5°, giving 3‐azidoazetidines 2 in good to excellent yields. After hydrogenolysis over Pd/C catalyst, compounds 2 were converted into N‐unsubstituted azetidin‐3‐amines 4 . Attempted reduction of 2a with Raney‐Ni led to a mixture of the expected azetidin‐3‐amine 4a and the ring‐enlarged 2,5‐dihydro‐1H‐imidazole derivative 5 . 相似文献
9.
Dr. Dongshun Ni Sai Hu Xiangyu Tan Dr. Yang Yu Dr. Zhenghua Li Prof. Li Deng 《Angewandte Chemie (International ed. in English)》2023,62(48):e202308606
Herein, we develop a new approach to directly access architecturally complex polycyclic indolines from readily available indoles and bicyclo[1.1.0]butanes (BCBs) through formal cycloaddition promoted by commercially available Lewis acids. The reaction proceeded through a stepwise pathway involving a nucleophilic addition of indoles to BCBs followed by an intramolecular Mannich reaction to form rigid indoline-fused polycyclic structures, which resemble polycyclic indole alkaloids. This new reaction tolerated a wide range of indoles and BCBs, thereby allowing the one-step construction of various rigid indoline polycycles containing up to four contiguous quaternary carbon centers. 相似文献
10.
Lee V. Ya. Miyazaki S. Gapurenko O. A. Minyaev R. M. Minkin V. I. Sekiguchi A. 《Russian Chemical Bulletin》2021,70(11):2233-2235
(Thiatrisila)bicyclo[1.1.0]butane 1 quantitatively transformed under either photochemical or thermal conditions into the isomeric (thiatrisila)cyclobutene 2, which was isolated and fully characterized.
相似文献11.
《Tetrahedron》1986,42(22):6201-6206
1,2,2-Trimethylbicyclo[1.1.0]butane reacted with excited state 1-cyanonaphthalene at a diffusion-controlled rate in methanol to produce cis- and trans-1-methoxy-2,2,3-trimethylcyclobutane and 1-methoxy-2, 2-dimethyl-3-methylenecyclobutane as simple methanol adducts of the starting bicy-clo[l.1.0]butane. In addition, 1:1:1 adducts of the starting bicyclo[1.1.0]butane, 1 -cyanonaphthalene, and methanol were isolated and characterized. Products were explained on the basis of a single electron transfer process from 1,2,2-trimethylbicyclo[1.1.0]butane to excited state 1-cyanonaphthalene to initially produce the cation radical of the bicyclo[1.1.0]butane and the anion radical of 1-cyanonaphthalene. 相似文献
12.
Lin Guo Adam Noble Varinder K. Aggarwal 《Angewandte Chemie (International ed. in English)》2021,60(1):212-216
The reaction of bicyclo[1.1.0]butyl pinacol boronic ester (BCB‐Bpin) with nucleophiles has been studied. Unlike BCBs bearing electron‐withdrawing groups, which react with nucleophiles at the β‐position, BCB‐Bpin reacts with a diverse set of heteroatom (O, S, N)‐centred nucleophiles exclusively at the α‐position. Aliphatic alcohols, phenols, carboxylic acids, thiols and sulfonamides were found to be competent nucleophiles, providing ready access to α‐heteroatom‐substituted cyclobutyl boronic esters. In contrast, sterically hindered bis‐sulfonamides and related nucleophiles reacted with BCB‐Bpin at the β′‐position leading to cyclopropanes with high trans‐selectivity. The origin of selectivity is discussed. 相似文献
13.
《Tetrahedron letters》1986,27(24):2739-2742
Azirines react with carbanions derived from α-chloro sulfones and sulfoxides, under mild conditions, to form functionalized azabicyclo[1.1.0]butanes. 相似文献
14.
Niklas Radhoff Dr. Constantin G. Daniliuc Prof. Dr. Armido Studer 《Angewandte Chemie (International ed. in English)》2023,62(34):e202304771
Design, synthesis and application of benzene bioisosteres have attracted a lot of attention in the past 20 years. Recently, bicyclo[2.1.1]hexanes have emerged as highly attractive bioisosteres for ortho- and meta-substituted benzenes. Herein we report a mild, scalable and transition-metal-free protocol for the construction of highly substituted bicyclo[2.1.1]hexan-2-ones through Lewis acid catalyzed (3+2)-cycloaddition of bicyclo[1.1.0]-butane ketones with disubstituted ketenes. The reaction shows high functional group tolerance as documented by the successful preparation of various 3-alkyl-3-aryl as well as 3,3-bisalkyl bicyclo[2.1.1]hexan-2-ones (26 examples, up to 89 % yield). Postfunctionalization of the exocyclic ketone moiety is also demonstrated. 相似文献
15.
Two new substituted [1.1.1]propellanes have been generated from the corresponding bicyclo[1.1.0]butanes in either single-step (1a) or four-step procedures (1b). The observed degree of double lithiation of the bicyclo[1.1.0]butanes is discussed in the context of DFT computational results. Addition reactions across the central C(1)-C(3) bonds of the propellanes were studied. Only the propellane 1b gave the biacetyl addition product. 相似文献
16.
Treatment of the bromobicyclo[1.1.0]butanes (=4)(=a) - (=c) with LDA led to the formation of the 1,2,3-butatrienes (=6) which were isomerized by excess base to the alkynes (=8). Reaction of [1-12-C](=4)(=c) with LDA afforded [3-12-C](=8)(=d), indicating that bicyclo[1.1.0]but-1(3)-ene (=5) was not an intermediate. 相似文献
17.
A Gallium‐Substituted Distibene and an Antimony‐Analogue Bicyclo[1.1.0]butane: Synthesis and Solid‐State Structures
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M. Sc. Lars Tuscher Dr. Chelladurai Ganesamoorthy Dieter Bläser Dr. Christoph Wölper Prof. Dr. Stephan Schulz 《Angewandte Chemie (International ed. in English)》2015,54(36):10657-10661
RGa {R=HC[C(Me)N(2,6‐iPr2C6H3)]2} reacts with Sb(NMe2)3 with insertion into the Sb? N bond and elimination of RGa(NMe2)2 ( 2 ), yielding the Ga‐substituted distibene R(Me2N)GaSb?SbGa(NMe2)R ( 1 ). Thermolysis of 1 proceeded with elimination of RGa and 2 and subsequent formation of the bicyclo[1.1.0]butane analogue [R(Me2N)Ga]2Sb4 ( 3 ). 相似文献
18.
Dr. Xu‐Qiong Xiao Zhaowen Dong Prof. Zhifang Li Chenting Yan Prof. Guoqiao Lai Prof. Mitsuo Kira 《Angewandte Chemie (International ed. in English)》2016,55(11):3758-3762
A 1,3‐diazasilabicyclo[1.1.0]butane ( 1 ) is synthesized as thermally stable crystals by using the cycloaddition reaction of an isolable dialkylsilylene with aziadamantane. The bridge N?N bond length of 1 (1.70 Å) is the longest among those of known N?N singly‐bonded compounds, including side‐on bridged transition‐metal dinitrogen complexes. The compound 1 is intact in air but moisture sensitive. No reaction occurs with hydrogen, even under pressure at 0.5 MPa. Irradiation of 1 with light gives an isomer quantitatively by N?N and adamantyl C?C bond cleavage. The origin of the remarkable N?N bond elongation is ascribed to significant interaction between a Si?C σ* and Ν?Ν π and σ orbitals as determined by DFT calculations of model compounds. 相似文献
19.
Ryan E. McNamee Marius M. Haugland Jeremy Nugent Rachel Chan Kirsten E. Christensen Edward A. Anderson 《Chemical science》2021,12(21):7480
Bicyclo[1.1.0]butanes (BCBs) are increasingly valued as intermediates in ‘strain release’ chemistry for the synthesis of substituted four membered rings and bicyclo[1.1.1]pentanes, with applications including bioconjugation processes. Variation of the BCB bridgehead substituents can be challenging due to the inherent strain of the bicyclic scaffold, often necessitating linear syntheses of specific BCB targets. Here we report the first palladium catalyzed cross-coupling on pre-formed BCBs which enables a ‘late stage’ diversification of the bridgehead position, and the conversion of the resultant products into a range of useful small ring building blocks.Bicyclo[1.1.0]butanes (BCBs) are valuable precursors to four-membered rings and bicyclo[1.1.1]pentanes, and useful bioconjugation agents. We describe a versatile approach to access 1,3-disubstituted BCBs, which are otherwise challenging to prepare. 相似文献
20.
Functionalization of P4 Using a Lewis Acid Stabilized Bicyclo[1.1.0]tetraphosphabutane Anion
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Jaap E. Borger Dr. Andreas W. Ehlers Dr. Martin Lutz Dr. J. Chris Slootweg Prof. Dr. Koop Lammertsma 《Angewandte Chemie (International ed. in English)》2014,53(47):12836-12839
Reacting white phosphorus (P4) with sterically encumbered aryl lithium reagents (aryl=2,6‐dimesitylphenyl or 2,4,6‐tBu3C6H2) and B(C6F5)3 gives the unique, isolable Lewis acid stabilized bicyclo[1.1.0]tetraphosphabutane anion. Subsequent alkylation of the nucleophilic site of the RP4 anion gives access to non‐symmetrical disubstituted bicyclic tetraphosphorus compounds. This novel method enables P? C bond formation in a controlled fashion using white phosphorus as starting material. 相似文献