Reference of 33100-27-5. Chemistry is an experimental science, and the best way to enjoy it and learn about it is performing experiments.Introducing a new discovery about 33100-27-5, Name is 1,4,7,10,13-Pentaoxacyclopentadecane
The cyclopentadienylboranes C5H5BR2 1-4 (R = NMe2, 1/2(OCMe2)2, Pri, Me) are synthesized from alkali metal cyclopentadienides MCp (M = Li, Na) and BCl(NMe2)2, ClB (OCMe2)2, BClPri2, and BBrMe2, respectively. Compound 1 reacts with lithium dialkylamides (LiNMe2, LDA, LiTMP) in THF or with elemental sodium to give the salts M[C5H5B(NMe2)2] [M(5) with M = Li, Na]. Compounds 2 and 3 are metalated by LiTMP, and compounds 3 and 4 by cyclopentadienides MCp (M = Li, Na) to give borylcyclopentadienides or boratafulvenes M[C5H5BR2] M(6)-M(8) (R = 1/2(OCMe2)2, Pri, Me). Estimated (NMR) room temperature equilibrium constants for the systems 1-4/LiCp in THF are 0.5, 4, >300, and >300, respectively; they show that dialkylboryl substituents stabilize cyclopentadienide ions markedly. The triclinic THF solvate Na(THF)(5) (=10) forms an approximately trigonal helix with alternating Na(THF)+ and anion units, while the tetragonal tetrahydropyran solvate Na(THP)(S) (?11) forms a tetragonal helix. The monoclinic solvate Li(12-crown-4)-(6) (?12) is molecular, and the orthorhombic Na(THP)2(S) (?13) displays a chain structure. The B-C1 distances [154.5(2) for 11, 148.8(8) for 12, and 150.8(4) pm for 13], lengthened C1-C2/C1-C5 distances (av) (142.5 for 11, 142.1 for 12, and 143.6 pm for 13), slightly lengthened C3-C4 distances (140.0 for 11, 141.1 for 12, and 143.5 pm for 13), and shortened C2-C3/C4-C5 distances (av) (140.3 for 11, 137.3 for 12, and 137.9 pm for 13) are caused by pi interactions (11 < 12, 13) between the C5 ring and the boryl function. These interactions are weak in the case of the B(NMe2)2 group and quite marked for the B(OCMe2)2 and BMe2 groups. If you are hungry for even more, make sure to check my other article about 33100-27-5. Reference of 33100-27-5
Reference：
Chiral Catalysts,
Chiral catalysts – SlideShare