Cómo asignar valores de NSMutableDictionary a NSArray

Estoy haciendo un análisis JSON y quiero mostrar mis datos analizados en unaUITableView.

Para eso, estoy tratando de asignar datos analizados deNSMutableDictionary aNSArray para mostrar en la vista de tabla, pero la matriz devuelvenull.

Aquí vuelve mi matriznull valor;

NSMutableDictionary *tempDict1;
NSArray *arr = [[tempDict1 valueForKey:@"rates"]  componentsSeparatedByString:@";"];

código

- (void)connectionDidFinishLoading:(NSURLConnection *)connection 
{
    [connection release];

    NSString *responseString = [[NSString alloc] initWithData:responseData encoding:NSUTF8StringEncoding];
    self.responseData = nil;

    //    NSArray *latestrates = [[responseString JSONValue] objectForKey:@"rates"];
    [responseString release];

    values = [responseString JSONValue];
    array = [[NSMutableArray alloc] init];
    array = [values valueForKey:@"rates"];
    NSLog(@"array values:--> %@",array);


    tempDict1 = (NSMutableDictionary *)array;  
    arr = [[tempDict1 valueForKey:@"rates"]  componentsSeparatedByString:@";"];
    NSString *subStar = @"=";
    NSMutableArray *arrTitle = [[NSMutableArray alloc] init];
    NSMutableArray *arrValues = [[NSMutableArray alloc] init];
    [arrTitle removeAllObjects];
    [arrValues removeAllObjects];
    for (int i=0; i<[arr count]-1; i++)
    {
        [arrTitle addObject:[[arr objectAtIndex:i] substringToIndex:NSMaxRange([[arr objectAtIndex:i] rangeOfString:subStar])-1]];
        [arrValues addObject:[[arr objectAtIndex:i] substringFromIndex:NSMaxRange([[arr objectAtIndex:i] rangeOfString:subStar])]];
        NSLog(@"arrTitle is:--> %@",arrTitle);
    }

    tempDict1 = (NSMutableDictionary*)[array objectAtIndex:0];
    array = [values valueForKey:@"rates"];
    NSLog(@"tempDict--%@",tempDict1);

    [arr retain];
    [tbl_withData reloadData];

}