Efficient syntheses are reported for tetraiodotetrathiafulvalene 2, 4-iodo-5-methyl-4',5'-bis(methylsulfanyl)TTF 3, and 4-iodo-4',5'-bis(methylsulfanyl)TTF 4 by iodination, using perfluorohexyl iodide, of lithiated derivatives of the corresponding TTF system. Bromination and chlorination of lithiotrimethylTTF using 1,2-dibromotetrafluoroethane and hexachloroethane gave 4-bromo-and 4-chloro-4',5,5'-trimethylTTF 6 and 7, respectively. Phosphite-induced self-coupling or cross-coupling reactions of 4-iodo-1,3-dithiole-2-thione or 4,5-diiodo-1,3-dithiole-2-thione(one) half-units resulted in TTF derivatives with partial loss of the iodine substituent(s). 4,5-Dibromo-4',5'-bis(cyanoethylsulfanyl)TTF 15 was prepared by cross-coupling methodology, and converted into 4,5-dibromo-4',5'-bis(methylsulfanyl)TTF 16 by reaction with caesium hydroxide and then methyl iodide. EPR data are reported for the electrochemically generated cation radicals of trimethylTTFX derivatives (X~I, Br and Cl) 5-7, respectively. For the neutral donors, the X-ray crystal structures are reported for 2, 5, 6, tetramethylTTF 8 and 15. Structure 2 is characterised by a particularly dense packing with continuous chains of intra-stack I … I contacts (4.17-4.19 A ˚). The crystals of 6 and 8 are isomorphous, while the structure of 5 is different. The iodo-substituent in 5 affects the packing in a way the bromo-substituent in 6 does not, due to differences in specific interactions rather than steric demands of I and Br, which are similar. Structure 15 comprises face-to-face dimers with inter-dimer Br … Br (3.57 A ˚) and Br … S (3.55 A ˚) contacts: a remarkable difference in bond distances between the Br and S-substituted dithiole rings is observed. The 1 : 1 charge-transfer (CT) complexes 3?TCNQ and 4?TCNQ (TCNQ~7,7,8,8-tetracyano-p-quinodimethane, 17) display mixed stair-like stacks of alternating D and A moieties: the overall degree of CT is estimated from bond length analysis to be 0.2 e and 0.3 e, respectively. In 3?TCNQ either position of the disordered iodine atom has one short (inter-stack, but intra-layer) contact with a cyano group (I … N distances of 3.14 and 3.18 A ˚). In 4?TCNQ a similar I … N contact is much longer (3.35 A ˚). In the structure of 5 z? I 3 2 ? 1 2I2 the cation radical is disordered; dimeric cation radicals display short intra-dimer contacts (S … S 3.38-3.39 A ˚, C … C 3.35 A ˚) consistent with electron coupling. Each dimer is surrounded by four I 3 2 anions. The crystal structure of 16 z? I 3 2 is comprised of layers with interplanar separations of 3.55 A ˚. Cations of one layer overlap with anions of the next, and the packing can be described as mixed stacks parallel to the a axis. The remarkably high conductivity of this salt for a system of 1 : 1 stoichiometry (s rt ~8610 22 S cm 21 ) is ascribed to partial charge transfer (the charge on the TTF moiety is estimated as z 2 3 from bond length analysis) and a continuous system of short non-bonding contacts.

Background This study assessed whether a Learning Disability Service should develop a specific autism strategy or provide services on a needs-led basis. Materials and methods An autism screening questionnaire had been used to identify individuals scoring above a cut-off who had (n ¼ 9) or had not (n ¼ 15) received a formal diagnosis of autism. A sample of low scorers (n ¼ 22) were matched to these groups. Questionnaires assessing service provision, needs (disabilities and challenging behaviour), quality of life and knowledge of autism were sent to relatives of individuals living at home or key-workers for those living in supported housing. Results The high scoring groups had similar levels of needs. Those diagnosed with autism received more services in total while the high scoring group without autism diagnoses scored significantly lower on quality of life. Although these differences were not maintained when level of disability was taken into account, it appeared that there was some level of unmet need in the high scorers without autism diagnoses group.Conclusions It appeared that resources should be targeted at identifying and addressing the specific needs of individuals presenting with autistic spectrum difficulties.

We report our investigations into tetrathiafulvalene (TTF) derivatives bearing N-methylthiocarbamoyl and halogen substituents which engage in intermolecular interactions in the solid state. The synthesis of new donors is presented, along with the X-ray crystal structures of some of these derivatives and their radical ion salts.