Stereochemistry of a spherand-type calixarene

被引：9
作者：
Agbaria, K
Biali, SE
Böhmer, V
Brenn, J
Cohen, S
Frings, M
Grynszpan, F
Harrowfield, JM
Sobolev, AN
Thondorf, I
机构：
[1] Univ Halle Wittenberg, Fachbereich Biochem Biotechnol, Inst Biochem, D-06099 Halle, Germany
[2] Hebrew Univ Jerusalem, Dept Organ Chem, IL-91904 Jerusalem, Israel
[3] Univ Mainz, Abt Lehramt Chem, Fachbereich Chem & Pharm, D-55099 Mainz, Germany
[4] Univ Western Australia, Dept Chem, Crawley, WA 6009, Australia
来源：
JOURNAL OF ORGANIC CHEMISTRY | 2001年 / 66卷 / 09期
关键词：
D O I：
10.1021/jo0016576
中图分类号：
O62 [有机化学];
学科分类号：
070303 ; 081704 ;
摘要：
The stereochemistry of the spherand-type calixarene 2a is analyzed in terms of the configuration of the three 2,2 ' -dihydroxybiphenyl subunits (R or S) and the disposition of the methylene groups (crown or twist). X-ray crystallography indicates that the neutral as and its mono- or dianion (in form of the salts 2a(-).C5H5NH+ and 2a(2-). 2Et(3)NH(+)) exist essentially in the same conformation (RRS/SSR-twist). This asymmetric RRS/SSR-twist form is the lowest energy conformer according to molecular mechanics calculations. Low-temperature H-1 NMR data indicate the presence of a major conformer of C-1 symmetry, in agreement with a RRS/SSR-twist form. The lowest energy topomerization pathway mutually exchanges two pairs of methylene protons and is ascribed to an enantiomerization process involving rotation around an Ar-Ar bond.
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页码：2900 / 2906
页数：7
相关论文
共 35 条
[1]   MOLECULAR MECHANICS - THE MM3 FORCE-FIELD FOR HYDROCARBONS .1. [J].
ALLINGER, NL ;
YUH, YH ;
LII, JH .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1989, 111 (23) :8551-8566
[2]   STRUCTURE AND BARRIER OF INTERNAL-ROTATION OF BIPHENYL DERIVATIVES IN THE GASEOUS STATE .1. THE MOLECULAR-STRUCTURE AND NORMAL COORDINATE ANALYSIS OF NORMAL BIPHENYL AND PERDEUTERATED BIPHENYL [J].
ALMENNINGEN, A ;
BASTIANSEN, O ;
FERNHOLT, L ;
CYVIN, BN ;
CYVIN, SJ ;
SAMDAL, S .
JOURNAL OF MOLECULAR STRUCTURE, 1985, 128 (1-3) :59-76
[3]   CRYSTAL AND MOLECULAR-STRUCTURE OF CYCLO(QUATER[(5-TERT-BUTYL-2-HYDROXY-1,3-PHENYLENE)METHYLENE]) TOLUENE (1-1) CLATHRATE [J].
ANDREETTI, GD ;
UNGARO, R ;
POCHINI, A .
JOURNAL OF THE CHEMICAL SOCIETY-CHEMICAL COMMUNICATIONS, 1979, (22) :1005-1007
[4]  
[Anonymous], COMPREHENSIVE SUPRAM
[5]  
[Anonymous], 2001, Calixarenes
[6]   Conformation, inversion barrier, and solvent-induced conformational shift in exo- and endo/exo-calix[4]arenes [J].
Biali, SE ;
Bohmer, V ;
Brenn, J ;
Frings, M ;
Thondorf, I ;
Vogt, W ;
Wohnert, J .
JOURNAL OF ORGANIC CHEMISTRY, 1997, 62 (24) :8350-8360
[7]   Alkanediyl bridged calix[4]arenes: Synthesis, conformational analysis, and rotational barriers [J].
Biali, SE ;
Bohmer, V ;
Cohen, S ;
Ferguson, G ;
Gruttner, C ;
Grynszpan, F ;
Paulus, EF ;
Thondorf, I ;
Vogt, W .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1996, 118 (51) :12938-12949
[8]   CALIXARENES, MACROCYCLES WITH (ALMOST) UNLIMITED POSSIBILITIES [J].
BOHMER, V .
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION IN ENGLISH, 1995, 34 (07) :713-745
[9]   SYSTEMATIC EFFECTS OF CRYSTAL-PACKING FORCES - BIPHENYL FRAGMENTS WITH H-ATOMS IN ALL 4 ORTHO POSITIONS [J].
BROCK, CP ;
MINTON, RP .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1989, 111 (13) :4586-4593
[10]   VALIDATION OF THE GENERAL-PURPOSE TRIPOS 5.2 FORCE-FIELD [J].
CLARK, M ;
CRAMER, RD ;
VANOPDENBOSCH, N .
JOURNAL OF COMPUTATIONAL CHEMISTRY, 1989, 10 (08) :982-1012
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