The identification of genes of agronomic interest in bread wheat (Triticum aestivum L.) is hampered by its allopolyploid nature (2n = 6x = 42; AABBDD) and its very large genome, which is largely covered by transposable elements. However, owing to this complex structure, aneuploid stocks can be developed in which fragments or entire chromosomes are missing, sometimes resulting in visible phenotypes that help in the cloning of affected genes. In this study, the 2C gametocidal chromosome from Aegilops cylindrica was used to develop a set of 113 deletion lines for chromosome 3D in the reference cultivar Chinese Spring. Eighty-four markers were used to show that the deletions evenly covered chromosome 3D and ranged from 6.5 to 357 Mb. Cytogenetic analyses confirmed that the physical size of the deletions correlated well with the known molecular size deduced from the reference sequence. This new genetic stock will be useful for positional cloning of genes on chromosome 3D, especially for Ph2 affecting homoeologous pairing in bread wheat.

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Synthesis of monomeric Cu complexes stabilized by the N!Ge coordinated germylene L(Cl)Ge (L = 2-Et 2 NCH 2 -4,6-tBu 2 -C 6 H 2 ) is reported. The reactions of the [L(Cl)Ge] 2 CuI (1) with AgX provided the complexes [L(Cl)Ge] 2 CuX (X = 2: X = OAc, 3: X = OTf) by selective substitution of the CuI bond. In contrast, the reaction of 1 with K[BEt 3 H] provided [L(H)Ge] 2 CuI (4), the product of selective substitution of the GeCl bonds. The 4 represents the first example of Cu complex stabilized by two organogermaniun hydrides [L(H)Ge].

N-coordinated Ge(II) alkoxides L 1 (tBuO)Ge (1), L 2 (tBuO)Ge ( 2) and [L 2 (OtBu)Ge • BH 3 ] (4) were prepared. Effect of either chelating ligands L 1 and L 2 or Ge!B interaction on strength of the GeÀ OtBu bond was studied by insertion reaction of PhNCO. As a result, the Ge(II) carbamate L 2 {[(tBuO)OC](Ph)N}Ge (3) was isolated. Alcoholysis exchange reactions of 1 and 2 with substituted phenols were studied to find an easy synthetic protocol for a synthesis of functionalized Ge(II) alkoxides. Reactions yielded Ge(II) alkoxides L 1,2 (2-BrÀ C 6 H 4 O)Ge (5 for L 1 , 8 for L 2 ), L 1,2 (2-MeNHÀ C 6 H 4 O)Ge (6 for L 1 , 9 for L 2 ), L 1,2 (2-Ph 2 PÀ C 6 H 4 O)Ge (7 for L 1 , 10 for L 2 ), L 2 (2-Br-3-OHÀ C 6 H 3 O)Ge ( 11) and L 2 (2-NC 5 H 4 O)Ge (12) containing the additional polar groups Y (Y = Br, MeNH, PPh 2 , OH or N). Finally, phosphane decorated Ge(II) alkoxides 7 and 10 were tested as suitable ligands in reactions with (COD)W(CO) 4 and BH 3 . As a consequence, new complexes [(k 2 -7)W(CO) 4 ] (13) and [L 1 (2-Ph 2 P • {BH 3 }-C 6 H 4 O)Ge • {BH 3 }] (14) were isolated. All compounds were characterized by NMR and IR spectroscopy, and compounds 3, 4, 9 and 11 were additionally characterized by X-ray diffraction analysis.

Reactivity studies of the GeII→B complex L(Cl)Ge⋅BH3 (1; L=2‐Et2NCH2‐4,6‐tBu2‐C6H2) were performed to determine the effect on the GeII→B donation. N‐coordinated compounds L(OtBu)Ge⋅BH3 (2) and [LGe⋅BH3]2 (3) were prepared. The possible tuning of the GeII→B interaction was proved experimentally, yielding compounds 1‐PPh2‐8‐(LGe)‐C10H6 (4) and L(Cl)Ge⋅GaCl3 (5) without a GeII→B interaction. In 5, an unprecedented GeII→Ga coordination was revealed. The experimental results were complemented by a theoretical study focusing on the bonding in 1−5. The different strength of the GeII→E (E=B, Ga) donation was evaluated by using energy decomposition analysis. The basicity of different L(X)Ge groups through proton affinity is also assessed.