Search

The Kutch region of western India (Gujarat State) is today arid to semiarid and characterised by mostly ephemeral streams which carry water during the monsoon. The uneven distribution of rainfall and disturbed topography are the result of climate change during the Cenozoic period. Two fossil woods, namelyBauhinium palaeomalabaricumPrakash and Prasad (Fabaceae) andEbenoxylon indicumGhosh and Kazmi (Ebenaceae), are described from Kutch in order to provide insights into the palaeovegetation and palaeoclimate. Because the modern representatives of the present and previously described taxa from the same horizon are thermophilic in nature and grow in evergreen to deciduous forests, a warm and humid climate is interpreted. Furthermore, the finding of some mangrove taxa in the assemblage indicates the lagoonal to intertidal environment at the time of deposition. [ABSTRACT FROM AUTHOR]

Reactions of bis(β-diketonato)aluminium(III)-di-μ-isopropoxo-di-isopropoxoaluminium(III), [(CH3COCHCOR)2Al-(μ-OPr-i)2Al(OPr-i)2] with 2-pyridylmethanol, (C5H4N-2-CH2OH) in 1:1 and 1:2 molar ratios in refluxing anhydrous benzene resulted in the synthesis of [(CH3COCHCOR)2Al(μ-OPr-i)2Al(OCH2-2-C5H4N)(OPr-i)] [where R=CH3 (1), -OC2-H5 (3), and -C6H5 (5)] and [(CH3COCHCOR)2Al(μ-OPr-i)2Al(OCH2-2-C5H4N)2] [where R=CH3 (2), -OC2H5 (4), and -C6H5 (6)], respectively. All of these compounds are sharp melting solids and are soluble in a variety of organic solvents (e.g., benzene, chloroform and dimethyl sulfoxide) except [(CH3COCHCOOC2H5)2Al(μ-OPr-i)2Al(OCH2-2-C5H4N)2], which is insoluble in benzene but soluble in chloroform and dimethylsulfoxide. All of these derivatives show a dinuclear structure in benzene. All of the above derivatives have been characterized by elemental analyses, molecular weight determinations, IR and NMR (1H, 13C and 27Al) and FAB mass spectral studies. [ABSTRACT FROM AUTHOR]

Reactions of bis (β-diketonato) aluminium(III)-di-μ-isopropoxo-di-isopropoxo-aluminium (III), [CH 3 COCHCOR) 2 Al(μ-OPr i ) 2 Al(OPr i ) 2 ], with triphenylsilanol, Ph 3 SiOH, in 1∶1 and 1∶2 molar ratios and with diphenylsilanediol, Ph 2 Si(OH) 2 , in a 1∶1 molar ratio, have resulted in the synthesis of [(CH 3 COCHCOR) 2 Al(μ-OPr i ) 2 Al(OSiPh 3 )(OPr i )], [(CH 3 COCHCOR) 2 Al(μ-OPr i ) 2 Al(OSiPh 3 ) 2 ] and [(CH 3 COCHCOR) 2 Al(μ-OPr i ) 2 ], respectively. These are soluble in a variety of organic solvents ( e.g. , benzene, chloroform and dimethylsulfoxide) and show dinuclear behaviour in chloroform. These derivatives have been characterized by elemental analyses, molecular weight measurements, IR and NMR ( 1 H, 13 C and 27 Al) studies. [ABSTRACT FROM AUTHOR]