Structure of tetraspiro[1,3,5,7-tetraoxa-2,4,6,8-tetragermacyclooctane-2,1':4,1'':6,1''':8,1''''-tetrakisgerminane]

Abstract

Abstract. C20H4oGe404, Mr=634.89, monoclinic,

Structural and Functional Evolution of Metallacrowns

“…These metallamacrocycles typically have either a square or rectangular shape, although the polygon can be slightly distorted in many instances. 8-MC-4 complexes with oxygen atom connectivity have been synthesized with Li I , 560 Al III , [561][562][563] Ti IV (Figure 94), [564][565][566][567][568][569][570][571][572][573][574][575][576][577][578][579][580] V IV , 581,582 V V , 583-587 mixed-valent V IV 2 V V 2 , 588,589 Mn II , 590 Mn III , 591,592 mixed-valent Mn II Mn III 3 , 593,594 Fe III , [595][596][597][598][599][600][601] Co II , 590 Ni II , 602,603 Cu I , [604][605][606][607] Cu II , 590,608-619 Zn II , 602,620-625 Ge IV , 626,627 Nb IV , 628 Nb V , [629][630][631]...…”

“…These metallamacrocycles typically have either a square or rectangular shape, although the polygon can be slightly distorted in many instances. 8-MC-4 complexes with oxygen atom connectivity have been synthesized with Li I , Al III , − Ti IV (Figure ), − V IV , , V V , − mixed-valent V IV 2 V V 2 , , Mn II , Mn III , , mixed-valent Mn II Mn III 3 , , Fe III , − Co II , Ni II , , Cu I , − Cu II , ,− Zn II , ,− Ge IV , , Nb IV ,…”

Germanium Organometallic Compounds: Classification and Analysis of Crystallographic and Structural Data

“…Theie are, however, significant differences in the ring structure between [Ge(ji-0){CH 2 ) 5 }] 4 [316] and Ge^-OXPh),] 4 [31 η. In the former the non-bonding distances average to 409.7(l o ) pm which is shorter than in the latter (443.4(7) pm.…”

“…Another four colourless derivatives [316,317] contain tetra-germa-tetra-oxacydooctane rin^ which adopt a "skewed tub" conformation. Theie are, however, significant differences in the ring structure between [Ge(ji-0){CH 2 ) 5 }] 4 [316] and Ge^-OXPh),] 4 [31 η.…”